WENTWORTH ENERGY, INC. Amended and Restated Secured ConvertibleDebenture Due: January 11, 2009

Exhibit 4.23

Dated:    October 31, 2007

Original Issue Date:  February 10, 2006

NEITHER THIS DEBENTURE NOR THE SECURITIES INTO WHICH THIS DEBENTURE IS CONVERTIBLE HAVE BEEN REGISTERED WITH THE SECURITIES AND EXCHANGE COMMISSION OR THE SECURITIES COMMISSION OF ANY STATE IN RELIANCE UPON AN EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), AND, ACCORDINGLY, MAY NOT BE OFFERED OR SOLD EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OR PURSUANT TO AN AVAILABLE EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND IN ACCORDANCE WITH APPLICABLE STATE SECURITIES LAWS.

WENTWORTH ENERGY, INC.

Amended and Restated Secured Convertible Debenture

Due: January 11, 2009

This Amended and Restated Secured Convertible Debenture (this “Debenture”) is issued by WENTWORTH ENERGY, INC., an Oklahoma corporation (the “Obligor”), to YA GLOBAL INVESTMENTS, L.P., a Cayman Islands exempt limited partnership (the “Holder”), pursuant to that certain Securities Purchase Agreement, dated as of January 12, 2006, by and between the Obligor and the Holder, as amended by that certain Amendment and Exchange Agreement, dated as of October 31, 2007 (“A&E Agreement”), by and between the Obligor and the Holder (as the same may be further amended, modified or supplemented from time to time, the “Securities Purchase Agreement”).

The Obligor and the Holder hereby agree that this Debenture is issued in exchange for, and does hereby amend and restate, and completely replace, that certain Debenture, dated as of February 10, 2006, by and between the Obligor and the Holder, which shall have no further force or effect.

FOR VALUE RECEIVED, the Obligor hereby promises to pay to the Holder or its successors and assigns the principal sum of [                                ] together with accrued but unpaid interest on or before January 11, 2009 (the “Maturity Date”) in accordance with the following terms:

Interest. Interest shall accrue on the outstanding principal balance hereof at an annual rate equal to ten percent (10%) commencing as of the date hereof. Interest shall be calculated on

the basis of a 360-day year and the actual number of days elapsed, to the extent permitted by applicable law. Interest hereunder will be paid to the Holder or its assignee in whose name this Debenture is registered on the records of the Obligor regarding registration and transfers of Debentures (the “Debenture Register”).

Right of Redemption. The Obligor at its option shall have the right, with five (5) Trading Days advance written notice (the “Redemption Notice” and the date of the Redemption Notice, the “Redemption Notice Date”), to redeem a portion or all amounts outstanding under this Debenture prior to the Maturity Date. The Obligor shall pay an amount equal to the principal amount being redeemed plus accrued interest, plus a redemption premium (“Redemption Premium”) equal to the product of (a) the positive difference, if any, between (x) the lowest Volume Weighted Average Price of the Common Stock during the five (5) Trading Days immediately preceding the Redemption Notice Date as quoted by Bloomberg, LP and (y) the Conversion Price (as defined in Section 3(c)(i)) on the Redemption Notice Date and (b) the quotient obtained by dividing (x) the outstanding principal amount plus accrued interest of this Debenture to be redeemed by (y) the Conversion Price on the Redemption Notice Date (collectively referred to as the “Redemption Amount”). The Obligor shall deliver to the Holder the Redemption Amount on the fifth (5^th) Trading Day following the Redemption Notice Date.

Notwithstanding the foregoing in the event that the Obligor has elected to redeem a portion of the outstanding principal amount and accrued interest under this Debenture the Holder shall be permitted to convert all or any portion of this Debenture after receipt of a Redemption Notice and prior to receiving the corresponding Redemption Amount.

Security Agreements. This Debenture is secured by that certain Security Agreement, dated as of January 12, 2006, by and between the Obligor and the Holder, as amended by the A&E Agreement (as further amended, modified or supplemented from time to time, the “Security Agreement”).

This Debenture is subject to the following additional provisions:

Section 1.              This Debenture is exchangeable for an equal aggregate principal amount of Debentures of different authorized denominations, as requested by the Holder surrendering the same. No service charge will be made for such registration of transfer or exchange.

Section 2.              Events of Default.

(a)           An “Event of Default”, wherever used herein, means any one of the following events (whatever the reason and whether it shall be voluntary or involuntary or effected by operation of law or pursuant to any judgment, decree or order of any court, or any order, rule or regulation of any administrative or governmental body):

(i)            Any default in the payment of the principal of, interest on or other charges in respect of this Debenture, as and when the same shall become due and payable (whether on a Conversion Date or the Maturity Date or by acceleration or otherwise);

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(ii)           The Obligor breaches any representation, warranty, covenant or other term or condition of any Transaction Document (as defined in Section 5), except, in the case of a breach of a covenant or other term or condition of any Transaction Document which is curable, only if such breach continues for a period of at least ten (10) consecutive Business Days;

(iii)          The Obligor or any of its Subsidiaries, pursuant to or within the meaning of Title 11, U.S. Code, or any similar Federal, foreign or state law for the relief of debtors (collectively, “Bankruptcy Law”), (A) commences a voluntary case, (B) consents to the entry of an order for relief against it in an involuntary case, (C) consents to the appointment of a receiver, trustee, assignee, liquidator or similar official (a “Custodian”), (D) makes a general assignment for the benefit of its creditors or (E) admits in writing that it is generally unable to pay its debts as they become due;

(iv)          a court of competent jurisdiction enters an order or decree under any Bankruptcy Law that (A) is for relief against the Company or any of its Subsidiaries in an involuntary case, (B) appoints a Custodian of the Company or any of its Subsidiaries for all or substantially all of its property or (C) orders the liquidation of the Company or any of its Subsidiaries and, in each case, such order or decree is not dismissed or stayed within thirty (30) days of such entry;

(v)           The Obligor or any Subsidiary of the Obligor shall default in any of its obligations under any other debenture or any mortgage, credit agreement or other facility, indenture agreement, factoring agreement or other instrument under which there may be issued, or by which there may be secured or evidenced any indebtedness for borrowed money or money due under any long term leasing or factoring arrangement of the Obligor or any Subsidiary of the Obligor in an amount exceeding $500,000 (other than the Senior Secured Financing Documents), whether such indebtedness now exists or shall hereafter be created and such default shall result in such indebtedness becoming or being declared due and payable prior to the date on which it would otherwise become due and payable;

(vi)          The Common Stock shall cease to be quoted for trading or listed for trading on either the Nasdaq OTC Bulletin Board (“OTC”), Nasdaq Capital Market, New York Stock Exchange, American Stock Exchange or the NASDAQ Global Market (each, a “Subsequent Market”) and shall not again be quoted or listed for trading on the OTC or a Subsequent Market within five (5) Trading Days of such delisting;

(vii)         The Obligor or any Subsidiary of the Obligor shall be a party to any Change of Control Transaction (as defined in Section 5);

(viii)        The Obligor shall fail for any reason to deliver Common Stock certificates to a Holder prior to the fifth (5^th) Trading Day after a Conversion Date or the Obligor shall provide notice to the Holder, including by way of public announcement, at any time, of its intention not to comply with requests for conversions of this Debenture in accordance with the terms hereof;

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(ix)           An “Event of Default” shall have occurred and be continuing under and as defined in the Senior Secured Convertible Notes; and

(x)            The Obligor shall fail for any reason to deliver the payment in cash pursuant to a Buy-In (as defined herein) within three (3) days after notice is claimed delivered hereunder.

(b)           During the time that any portion of this Debenture is outstanding, if any Event of Default has occurred, the full principal amount of this Debenture, together with interest and other amounts owing in respect thereof, to the date of acceleration shall become at the Holder’s election, immediately due and payable in cash, provided however, the Holder may request (but shall have no obligation to request) payment of such amounts in Common Stock of the Obligor. In addition to any other remedies, the Holder shall have the right (but not the obligation) to convert this Debenture at any time after an Event of Default, including after the Maturity Date, at the Conversion Price then in-effect. The Holder need not provide and the Obligor hereby waives any presentment, demand, protest or other notice of any kind, and the Holder may immediately and without expiration of any grace period enforce any and all of its rights and remedies hereunder and all other remedies available to it under applicable law. Such declaration may be rescinded and annulled by the Holder at any time prior to payment hereunder. No such rescission or annulment shall affect any subsequent Event of Default or impair any right consequent thereon. Upon an Event of Default, notwithstanding any other provision of this Debenture or any Transaction Document, the Holder shall have no obligation to comply with or adhere to, any limitations, if any, on the conversion of this Debenture or the sale of the Underlying Shares.

Section 3.              Conversion.

(a)           Conversion at Option of Holder.

(i)            This Debenture shall be convertible into shares of Common Stock at the option of the Holder, in whole or in part, at any time and from time to time, after the Original Issue Date (as defined in Section 5) (subject to the limitations on conversion set forth in Section 3(b) hereof). The number of shares of Common Stock issuable upon a conversion hereunder equals the quotient obtained by dividing (x) the outstanding amount of this Debenture to be converted by (y) the Conversion Price (as defined in Section 3(c)(i)). The Obligor shall deliver Common Stock certificates to the Holder prior to the fifth (5^th) Trading Day after a Conversion Date.

(ii)           Notwithstanding anything to the contrary contained herein, if on any Conversion Date: (1) the number of shares of Common Stock at the time authorized, unissued and unreserved for all purposes, or held as treasury stock, is insufficient to pay principal and interest hereunder in shares of Common Stock; (2) the Common Stock is not listed or quoted for trading on the OTC or on a Subsequent Market; (3) the Obligor has failed to timely satisfy its conversion; or (4) the issuance of such shares of Common Stock would result in a violation of Section 3(b), then, at the option of the Holder, the Obligor, in lieu of delivering shares of

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Common Stock pursuant to Section 3(a)(i), shall deliver, within three (3) Trading Days of each applicable Conversion Date, an amount in cash equal to the product of the outstanding principal amount to be converted plus any interest due thereon divided by the Conversion Price, chosen by the Holder, and multiplied by the highest closing price of the Common Stock from date of the Conversion Notice till the date that such cash payment is made.

Further, if the Obligor shall not have delivered any cash due in respect of conversion of this Debenture or as payment of interest thereon by the fifth (5^th) Trading Day after the Conversion Date, the Holder may, by notice to the Obligor, require the Obligor to issue shares of Common Stock pursuant to Section 3(c), except that for such purpose the Conversion Price applicable thereto shall be the lesser of the Conversion Price on the Conversion Date and the Conversion Price on the date of such Holder demand. Any such shares will be subject to the provisions of this Section.

(iii)          The Holder shall effect conversions by delivering to the Obligor a completed notice in the form attached hereto as Exhibit A (a “Conversion Notice”). The date on which a Conversion Notice is delivered is the “Conversion Date.” Unless the Holder is converting the entire principal amount outstanding under this Debenture, the Holder is not required to physically surrender this Debenture to the Obligor in order to effect conversions. Conversions hereunder shall have the effect of lowering the outstanding principal amount of this Debenture plus all accrued and unpaid interest thereon in an amount equal to the applicable conversion. The Holder and the Obligor shall maintain records showing the principal amount converted and the date of such conversions. In the event of any dispute or discrepancy, the records of the Holder shall be controlling and determinative in the absence of manifest error.

(b)           Certain Conversion Restrictions.

(i)            A Holder may not convert this Debenture or receive shares of Common Stock as payment of interest hereunder to the extent such conversion or receipt of such interest payment would result in the Holder, together with any affiliate thereof, beneficially owning (as determined in accordance with Section 13(d) of the Exchange Act and the rules promulgated thereunder) in excess of 4.9% of the then issued and outstanding shares of Common Stock, including shares issuable upon conversion of, and payment of interest on, this Debenture held by such Holder after application of this Section. Since the Holder will not be obligated to report to the Obligor the number of shares of Common Stock it may hold at the time of a conversion hereunder, unless the conversion at issue would result in the issuance of shares of Common Stock in excess of 4.9% of the then outstanding shares of Common Stock without regard to any other shares which may be beneficially owned by the Holder or an affiliate thereof, the Holder shall have the authority and obligation to determine whether the restriction contained in this Section will limit any particular conversion hereunder and to the extent that the Holder determines that the limitation contained in this Section applies, the determination of which portion of the principal amount of this Debenture is convertible shall be the responsibility and obligation of the Holder. If the Holder has delivered a Conversion Notice for a principal amount of this Debenture that, without regard to any other shares that the Holder or its affiliates may beneficially own, would result in the issuance in excess of the permitted amount hereunder, the

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Obligor shall notify the Holder of this fact and shall honor the conversion for the maximum principal amount permitted to be converted on such Conversion Date in accordance with the periods described in Section 3(a)(i) and, at the option of the Holder, either retain any principal amount tendered for conversion in excess of the permitted amount hereunder for future conversions or return such excess principal amount to the Holder.

(ii)           The Holder (a) shall not make any conversions of this Debenture at the Market Conversion Price during the first six (6) months following the date hereof, and (b) shall not, in any of the six separate thirty (30) day periods beginning on the six month anniversary of the date hereof and ending on the twelfth (12^th) month anniversary of the date hereof, convert this Debenture at the Market Conversion Price in an amount in excess of the greater of (y) $150,000 or (z) ten percent (10%) of the total dollar volume of the Common Stock traded on the OTC or any Subsequent Market according to Bloomberg, LP for the thirty (30) day period immediately prior to the applicable period. Notwithstanding the forgoing, these conversion restrictions shall not apply upon the occurrence of an Event of Default or if waived in writing by the Company. Nothing contained in this Section 3(b)(ii) hereof shall limit the Holder’s right to make conversions at the Fixed Conversion Price. The limitation set forth in this Section 3(b)(ii)(b) shall apply in total combined with any conversions at the Market Conversion Price on any other debentures issued pursuant to the Securities Purchase Agreement.

(c)           Conversion Price and Adjustments to Conversion Price.

(i)            The conversion price (the “Conversion Price”) in effect on any Conversion Date shall be equal to the lesser of (a) $0.65 (the “Fixed Conversion Price”) or (ii) eighty five percent (85%) of the lowest Volume Weighted Average Price of the Common Stock during the fifteen (15) Trading Days immediately preceding the Conversion Date as quoted by Bloomberg, LP (the “Market Conversion Price”). The Conversion Price may be adjusted pursuant to the other terms of this Debenture. For the six (6) month period following the date hereof, the Holder may only convert this Debenture by using the Fixed Conversion Price.

(ii)           If the Obligor, at any time while this Debenture is outstanding, shall (a) pay a stock dividend or otherwise make a distribution or distributions on shares of its Common Stock or any other equity or equity equivalent securities payable in shares of Common Stock, (b) subdivide outstanding shares of Common Stock into a larger number of shares, (c) combine (including by way of reverse stock split) outstanding shares of Common Stock into a smaller number of shares, or (d) issue by reclassification of shares of the Common Stock any shares of capital stock of the Obligor, then the Fixed Conversion Price shall be multiplied by a fraction of which the numerator shall be the number of shares of Common Stock (excluding treasury shares, if any) outstanding before such event and of which the denominator shall be the number of shares of Common Stock outstanding after such event. Any adjustment made pursuant to this Section shall become effective immediately after the record date for the determination of stockholders entitled to receive such dividend or distribution and shall become effective immediately after the effective date in the case of a subdivision, combination or re-classification.

(iii)          If the Obligor, at any time while this Debenture is outstanding, shall issue

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rights, options or warrants to all holders of Common Stock (and not to the Holder) entitling them to subscribe for or purchase shares of Common Stock at a price per share less than the Fixed Conversion Price, then the Fixed Conversion Price shall be multiplied by a fraction, of which the denominator shall be the number of shares of the Common Stock (excluding treasury shares, if any) outstanding on the date of issuance of such rights or warrants (plus the number of additional shares of Common Stock offered for subscription or purchase), and of which the numerator shall be the number of shares of the Common Stock (excluding treasury shares, if any) outstanding on the date of issuance of such rights or warrants, plus the number of shares which the aggregate offering price of the total number of shares so offered would purchase at the Fixed Conversion Price. Such adjustment shall be made whenever such rights or warrants are issued, and shall become effective immediately after the record date for the determination of stockholders entitled to receive such rights, options or warrants. However, upon the expiration of any such right, option or warrant to purchase shares of the Common Stock the issuance of which resulted in an adjustment in the Fixed Conversion Price pursuant to this Section, if any such right, option or warrant shall expire and shall not have been exercised, the Fixed Conversion Price shall immediately upon such expiration be recomputed and effective immediately upon such expiration be increased to the price which it would have been (but reflecting any other adjustments in the Fixed Conversion Price made pursuant to the provisions of this Section after the issuance of such rights or warrants) had the adjustment of the Fixed Conversion Price made upon the issuance of such rights, options or warrants been made on the basis of offering for subscription or purchase only that number of shares of the Common Stock actually purchased upon the exercise of such rights, options or warrants actually exercised.

(iv)          If the Obligor or any Subsidiary thereof, as applicable, at any time while this Debenture is outstanding, shall issue shares of Common Stock or rights, warrants, options or other securities or debt that are convertible into or exchangeable for shares of Common Stock (“Common Stock Equivalents”) entitling any Person to acquire shares of Common Stock, at a price per share less than the Fixed Conversion Price (if the holder of the Common Stock or Common Stock Equivalent so issued shall at any time, whether by operation of purchase price adjustments, reset provisions, floating conversion, exercise or exchange prices or otherwise, or due to warrants, options or rights per share which is issued in connection with such issuance, be entitled to receive shares of Common Stock at a price per share which is less than the Fixed Conversion Price, such issuance shall be deemed to have occurred for less than the Fixed Conversion Price), then, at the sole option of the Holder, the Fixed Conversion Price shall be adjusted to mirror the conversion, exchange or purchase price for such Common Stock or Common Stock Equivalents (including any reset provisions thereof) at issue. Such adjustment shall be made whenever such Common Stock or Common Stock Equivalents are issued. The Obligor shall notify the Holder in writing, no later than one (1) Business Day following the issuance of any Common Stock or Common Stock Equivalent subject to this Section, indicating therein the applicable issuance price, or of applicable reset price, exchange price, conversion price and other pricing terms.

(v)           If the Obligor, at any time while this Debenture is outstanding, shall distribute to all holders of Common Stock (and not to the Holder) evidences of its indebtedness or assets or rights or warrants to subscribe for or purchase any security, then in each such case the Fixed Conversion Price at which this Debenture shall thereafter be convertible shall be

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determined by multiplying the Fixed Conversion Price in effect immediately prior to the record date fixed for determination of stockholders entitled to receive such distribution by a fraction of which the denominator shall be the Closing Bid Price determined as of the record date mentioned above, and of which the numerator shall be such Closing Bid Price on such record date less the then fair market value at such record date of the portion of such assets or evidence of indebtedness so distributed applicable to one outstanding share of the Common Stock as determined by the Board of Directors in good faith. In either case the adjustments shall be described in a statement provided to the Holder of the portion of assets or evidences of indebtedness so distributed or such subscription rights applicable to one share of Common Stock. Such adjustment shall be made whenever any such distribution is made and shall become effective immediately after the record date mentioned above.

(vi)          In case of any reclassification of the Common Stock or any compulsory share exchange pursuant to which the Common Stock is converted into other securities, cash or property, the Holder shall have the right thereafter to, at its option, (A) convert the then outstanding principal amount, together with all accrued but unpaid interest and any other amounts then owing hereunder in respect of this Debenture into the shares of stock and other securities, cash and property receivable upon or deemed to be held by holders of the Common Stock following such reclassification or share exchange, and the Holder of this Debenture shall be entitled upon such event to receive such amount of securities, cash or property as the shares of the Common Stock of the Obligor into which the then outstanding principal amount, together with all accrued but unpaid interest and any other amounts then owing hereunder in respect of this Debenture could have been converted immediately prior to such reclassification or share exchange would have been entitled, or (B) require the Obligor to prepay the outstanding principal amount of this Debenture, plus all interest and other amounts due and payable thereon. The entire prepayment price shall be paid in cash. This provision shall similarly apply to successive reclassifications or share exchanges.

(vii)         All calculations under this Section 3 shall be rounded up to the nearest $0.001 or whole share.

(viii)        Whenever the Fixed Conversion Price is adjusted pursuant to Section 3 hereof, the Obligor shall promptly mail to the Holder a notice setting forth the Fixed Conversion Price after such adjustment and setting forth a brief statement of the facts requiring such adjustment.

(ix)           If (A) the Obligor shall declare a dividend (or any other distribution) on the Common Stock; (B) the Obligor shall declare a special nonrecurring cash dividend on or a redemption of the Common Stock; (C) the Obligor shall authorize the granting to all holders of the Common Stock rights or warrants to subscribe for or purchase any shares of capital stock of any class or of any rights; (D) the approval of any stockholders of the Obligor shall be required in connection with any reclassification of the Common Stock, any consolidation or merger to which the Obligor is a party, any sale or transfer of all or substantially all of the assets of the Obligor, of any compulsory share exchange whereby the Common Stock is converted into other securities, cash or property; or (E) the Obligor shall authorize the voluntary or involuntary

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dissolution, liquidation or winding up of the affairs of the Obligor; then, in each case, the Obligor shall cause to be filed at each office or agency maintained for the purpose of conversion of this Debenture, and shall cause to be mailed to the Holder at its last address as it shall appear upon the stock books of the Obligor, at least twenty (20) calendar days prior to the applicable record or effective date hereinafter specified, a notice stating (x) the date on which a record is to be taken for the purpose of such dividend, distribution, redemption, rights or warrants, or if a record is not to be taken, the date as of which the holders of the Common Stock of record to be entitled to such dividend, distributions, redemption, rights or warrants are to be determined or (y) the date on which such reclassification, consolidation, merger, sale, transfer or share exchange is expected to become effective or close, and the date as of which it is expected that holders of the Common Stock of record shall be entitled to exchange their shares of the Common Stock for securities, cash or other property deliverable upon such reclassification, consolidation, merger, sale, transfer or share exchange, provided, that the failure to mail such notice or any defect therein or in the mailing thereof shall not affect the validity of the corporate action required to be specified in such notice. The Holder is entitled to convert this Debenture during the 20-day calendar period commencing the date of such notice to the effective date of the event triggering such notice.

(x)            In case of any (1) merger or consolidation of the Obligor or any Subsidiary of the Obligor with or into another Person, or (2) sale by the Obligor or any Subsidiary of the Obligor of more than one-half of the assets of the Obligor in one or a series of related transactions, a Holder shall have the right to (A) exercise any rights under Section 2(b), (B) convert the aggregate amount of this Debenture then outstanding into the shares of stock and other securities, cash and property receivable upon or deemed to be held by holders of Common Stock following such merger, consolidation or sale, and such Holder shall be entitled upon such event or series of related events to receive such amount of securities, cash and property as the shares of Common Stock into which such aggregate principal amount of this Debenture could have been converted immediately prior to such merger, consolidation or sales would have been entitled, or (C) in the case of a merger or consolidation, require the surviving entity to issue to the Holder a convertible Debenture with a principal amount equal to the aggregate principal amount of this Debenture then held by such Holder, plus all accrued and unpaid interest and other amounts owing thereon, which such newly issued convertible Debenture shall have terms identical (including with respect to conversion) to the terms of this Debenture, and shall be entitled to all of the rights and privileges of the Holder of this Debenture set forth herein and the agreements pursuant to which this Debentures were issued. In the case of clause (C), the conversion price applicable for the newly issued shares of convertible preferred stock or convertible Debentures shall be based upon the amount of securities, cash and property that each share of Common Stock would receive in such transaction and the Conversion Price in effect immediately prior to the effectiveness or closing date for such transaction. The terms of any such merger, sale or consolidation shall include such terms so as to continue to give the Holder the right to receive the securities, cash and property set forth in this Section upon any conversion or redemption following such event. This provision shall similarly apply to successive such events. Notwithstanding any provision to the contrary contained in this Debenture, the provisions of this Section 3(c)(x) shall not apply to any merger or consolidation of or sale by the Obligor or any Subsidiary of the Obligor entered into in connection with a Company Full Mandatory

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Redemption(as defined in the Senior Secured Convertible Notes).

(xi)           Notwithstanding any provision to the contrary contained in this Debenture, no adjustment under this Section 3(c) shall be made as to the Fixed Conversion Price as a result of the issuance, grant, exercise or conversion of the Excluded Securities.

(d)           Other Provisions.

(i)            The Obligor covenants that it will at all times reserve and keep available out of its authorized and unissued shares of Common Stock solely for the purpose of issuance upon conversion of this Debenture and payment of interest on this Debenture, each as herein provided, free from preemptive rights or any other actual contingent purchase rights of persons other than the Holder, not less than such number of shares of the Common Stock as shall (subject to any additional requirements of the Obligor as to reservation of such shares set forth in this Debenture) be issuable (taking into account the adjustments and restrictions of Sections 2(b) and 3(c)) upon the conversion of the outstanding principal amount of this Debenture and payment of interest hereunder; and within three (3) Business Days following the receipt by the Obligor of a Holder’s notice that such minimum number of shares of Common Stock is not so reserved, the Obligor shall promptly reserve a sufficient number of shares of Common Stock to comply with such requirement. The Obligor covenants that all shares of Common Stock that shall be so issuable shall, upon issue, be duly and validly authorized, issued and fully paid, nonassessable.

(ii)           Upon a conversion hereunder the Obligor shall not be required to issue stock certificates representing fractions of shares of the Common Stock, but may if otherwise permitted, make a cash payment in respect of any final fraction of a share based on the Closing Bid Price at such time. If the Obligor elects not, or is unable, to make such a cash payment, the Holder shall be entitled to receive, in lieu of the final fraction of a share, one whole share of Common Stock.

(iii)          The issuance of certificates for shares of the Common Stock on conversion of this Debenture shall be made without charge to the Holder thereof for any documentary stamp or similar taxes that may be payable in respect of the issue or delivery of such certificate, provided that the Obligor shall not be required to pay any tax that may be payable in respect of any transfer involved in the issuance and delivery of any such certificate upon conversion in a name other than that of the Holder of such Debenture so converted and the Obligor shall not be required to issue or deliver such certificates unless or until the person or persons requesting the issuance thereof shall have paid to the Obligor the amount of such tax or shall have established to the satisfaction of the Obligor that such tax has been paid.

(iv)          Nothing herein shall limit a Holder’s right to pursue actual damages or declare an Event of Default pursuant to Section 2 herein for the Obligor’s failure to deliver certificates representing shares of Common Stock upon conversion within the period specified herein and such Holder shall have the right to pursue all remedies available to it at law or in equity including, without limitation, a decree of specific performance and/or injunctive relief, in each case without the need to post a bond or provide other security. The exercise of any such

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rights shall not prohibit the Holder from seeking to enforce damages pursuant to any other Section hereof or under applicable law.

(v)           In addition to any other rights available to the Holder, if the Obligor fails to deliver to the Holder such certificate or certificates pursuant to Section 3(a)(i) by the fifth (5^th) Trading Day after the Conversion Date, and if after such fifth (5^th) Trading Day the Holder purchases (in an open market transaction or otherwise) Common Stock to deliver in satisfaction of a sale by such Holder of the Underlying Shares which the Holder anticipated receiving upon such conversion (a “Buy-In”), then the Obligor shall (A) pay in cash to the Holder (in addition to any remedies available to or elected by the Holder) the amount by which (x) the Holder’s total purchase price (including brokerage commissions, if any) for the Common Stock so purchased exceeds (y) the product of (1) the aggregate number of shares of Common Stock that such Holder anticipated receiving from the conversion at issue multiplied by (2) the market price of the Common Stock at the time of the sale giving rise to such purchase obligation and (B) at the option of the Holder, either reissue a Debenture in the principal amount equal to the principal amount of the attempted conversion or deliver to the Holder the number of shares of Common Stock that would have been issued had the Obligor timely complied with its delivery requirements under Section 3(a)(i). For example, if the Holder purchases Common Stock having a total purchase price of $11,000 to cover a Buy-In with respect to an attempted conversion of Debentures with respect to which the market price of the Underlying Shares on the date of conversion was a total of $10,000 under clause (A) of the immediately preceding sentence, the Obligor shall be required to pay the Holder $1,000. The Holder shall provide the Obligor written notice indicating the amounts payable to the Holder in respect of the Buy-In.

(vi)          The Obligor represents that in no event shall any conversion under the Debenture at prices that are less than or equal to $0.65 trigger any adjustments, ratchets, or resets on any securities issued pursuant to the Senior Secured Financing Documents.

Section 4.              Notices. Any notices, consents, waivers or other communications required or permitted to be given under the terms hereof must be in writing and will be deemed to have been delivered: (i) upon receipt, when delivered personally; (ii) upon receipt, when sent by facsimile (provided confirmation of transmission is mechanically or electronically generated and kept on file by the sending party); or (iii) one (1) Trading Day after deposit with a nationally recognized overnight delivery service, in each case properly addressed to the party to receive the same. The addresses and facsimile numbers for such communications shall be:

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or at such other address and/or facsimile number and/or to the attention of such other person as the recipient party has specified by written notice given to each other party three (3) Business Days prior to the effectiveness of such change. Written confirmation of receipt (i) given by the recipient of such notice, consent, waiver or other communication, (ii) mechanically or electronically generated by the sender’s facsimile machine containing the time, date, recipient facsimile number and an image of the first page of such transmission or (iii) provided by a nationally recognized overnight delivery service, shall be rebuttable evidence of personal

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service, receipt by facsimile or receipt from a nationally recognized overnight delivery service in accordance with clause (i), (ii) or (iii) above, respectively.

Section 5.              Definitions. For the purposes hereof, the following terms shall have the following meanings:

“Approved Stock Plan” means any employee benefit plan, arrangement or other agreement which has been approved by the Board of Directors of the Company, pursuant to which the Company’s securities may be issued to any employee, consultant, officer or director for services provided to the Company.

“Business Day” means any day except Saturday, Sunday and any day which shall be a federal legal holiday in the United States or a day on which banking institutions are authorized or required by law or other government action to close.

“Change of Control Transaction” means the occurrence of (a) an acquisition after the date hereof by an individual or legal entity or “group” (as described in Rule l3d-5(b)(l) promulgated under the Exchange Act) of effective control (whether through legal or beneficial ownership of capital stock of the Obligor, by contract or otherwise) of in excess of fifty percent (50%) of the voting securities of the Obligor (except that the acquisition of voting securities by the Holder shall not constitute a Change of Control Transaction for purposes hereof), (b) a replacement at one time or over time of more than one-half of the members of the board of directors of the Obligor which is not approved by a majority of those individuals who are members of the board of directors on the date hereof (or by those individuals who are serving as members of the board of directors on any date whose nomination to the board of directors was approved by a majority of the members of the board of directors who are members on the date hereof), (c) the merger, consolidation or sale of fifty percent (50%) or more of the assets of the Obligor or any Subsidiary of the Obligor in one or a series of related transactions with or into another entity, or (d) the execution by the Obligor of an agreement to which the Obligor is a party or by which it is bound, providing for any of the events set forth above in (a), (b) or (c); provided, however, that notwithstanding any provision to the contrary contained in this Debenture, in no event shall any event or circumstance, transaction, agreement or arrangement of any kind entered into by the Company in connection with a Company Full Mandatory Redemption (as defined in the Senior Secured Convertible Notes) be a “Change of Control Transaction” for purposes of this Debenture.

“Commission” means the Securities and Exchange Commission.

“Common Stock” means the common stock, par value $.001, of the Obligor and stock of any other class into which such shares may hereafter be changed or reclassified.

“Conversion Date” means the date upon which the Holder gives the Obligor notice of their intention to effectuate a conversion of this Debenture into shares of the Company’s Common Stock as outlined herein.

“Convertible Securities” means any stock or securities (other than Options) directly or

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indirectly convertible into or exercisable or exchangeable for Common Stock

“Closing Bid Price” means the price per share in the last reported trade of the Common Stock on the OTC or on the exchange which the Common Stock is then listed as quoted by Bloomberg, LP.

“Exchange Act” means the Securities Exchange Act of 1934, as amended.

“Excluded Securities” means any Common Stock issued or issuable: (i) in connection with any Approved Stock Plan; (ii) upon conversion of this Debenture or any of the other Amended and Restated Convertible Debentures (as defined in the Securities Purchase Agreement) or upon conversion of the Senior Secured Convertible Notes or upon exercise of the Amended and Restated Warrants (as defined in the Securities Purchase Agreement) or the Warrants (as defined in the Other Securities Purchase Agreement); (iii) upon exercise of any Options or Convertible Securities which are outstanding, or that are subject to a written agreement as to their issuance that is listed on a schedule to the Other Securities Purchase Agreement; (iv) in an amount not to exceed 250,000 shares of Common Stock in the aggregate pursuant to a judgment or settlement in connection with (a) the PIN Financial Matter or (b) the UOS Energy Matter including, without limitation, Common Stock issuable pursuant to Options granted or Convertible Securities issued pursuant to such judgment or settlement; and (v) otherwise pursuant to a written agreement that is listed on a schedule to the Other Securities Purchase Agreement, provided that the terms of conversion price, exchange price, exercise or other purchase price therein are not amended, modified or otherwise changed after the date hereof to reduce the conversion price, exchange price, exercise or other purchase price below that in effect on the date hereof, and the terms of the number of shares of Common Stock issued or issuable therein are not amended, modified or changed after the date hereof to increase the number of shares of Common Stock issued or issuable above that in effect on the date hereof, by virtue of any amendment, modification or change to such Options or Convertible Securities or written agreements after the date hereof.

“Options” means any rights, warrants or options to subscribe for or purchase shares of Common Stock or Convertible Securities.

“Original Issue Date” means the initial date of this Debenture regardless of the number of transfers or amendments and regardless of the number of instruments which may be issued to evidence such Debenture.

“Other Securities Purchase Agreement” means that certain Securities Purchase Agreement dated as of July 24, 2006, by and among the Company and each of the buyers party thereto, as the same may be amended, modified or supplemented from time to time including, without limitation, by those certain Amendment Agreements, each dated as of October 31, 2007, by and between the Obligor and the buyer party thereto.

“Person” means a corporation, an association, a partnership, organization, a business, an individual, a government or political subdivision thereof or a governmental agency.

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“PIN Financial Matter” means the matter pending in the US District Court, Southern District of New York (06 CV 2779) against the Company by PIN Financial LLC claiming a commission for introduction to Cornell Capital Partners, LP, which has been aggressively denied and disputed by both Wentworth and Cornell Capital Partners, LP.

“Securities Act” means the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder.

“Senior Secured Convertible Notes” means those certain Amended and Restated Notes and New Note as defined in and issued by the Company pursuant to the Other Securities Purchase Agreement.

“Senior Secured Financing Documents” means the Other Securities Purchase Agreement and each other agreement entered into by the parties thereto in connection with the transactions contemplated thereby, including without limitation the Amended and Restated Notes, the New Notes, the Amended and Restated Warrants, the New Warrants, the Amended and Restated Registration Rights Agreement, the Amended and Restated Pledge Agreement, the Amended and Restated Security Agreement, the Amended and Restated Barnico Guaranty, and the Amended and Restated Deeds of Trust as each such term is defined therein.

“Subsidiary” means any entity in which the Company, directly or indirectly, owns a majority in voting power of the capital stock or equity or similar interests, provided that for purposes of this Debenture, Wentworth Oil and Gas, Inc. shall not be a Subsidiary.

“Trading Day” means a day on which the shares of Common Stock are quoted on the OTC or quoted or traded on such Subsequent Market on which the shares of Common Stock are then quoted or listed; provided, that in the event that the shares of Common Stock are not listed or quoted, then Trading Day shall mean a Business Day.

“Transaction Documents” has the meaning given to such term in the Securities Purchase Agreement.

“Underlying Shares” means the shares of Common Stock issuable upon conversion of this Debenture or as payment of interest in accordance with the terms hereof.

“UOS Energy Matter” means, the matter pending in the Superior Court of California, County of Los Angeles, West District (SC09064) against the Company and others by UOS Energy, LLC relating to the Company’s refusal to purchase certain tar sands leases in Utah in consideration of 1,000,000 shares of Common Stock.

“Volume Weighted Average Price” means, for any security as of any date, the daily dollar volume-weighted average price for such security as reported by Bloomberg through its “Historical Prices – Px Table with Average Daily Volume” functions, or, if no dollar volume-weighted average price is reported for such security by Bloomberg, the average of the highest

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closing bid price and the lowest closing ask price of any of the market makers for such security as reported in the “pink sheets” by Pink Sheets LLC.

Section 6.              Except as expressly provided herein, no provision of this Debenture shall alter or impair the obligations of the Obligor, which are absolute and unconditional, to pay the principal of, interest and other charges (if any) on, this Debenture at the time, place, and rate, and in the coin or currency, herein prescribed. This Debenture is a direct obligation of the Obligor. This Debenture ranks pari passu with all other Debentures now or hereafter issued under the terms set forth herein. As long as this Debenture is outstanding, the Obligor shall not and shall cause its Subsidiaries not to, without the consent of the Holder, (i) amend its certificate of incorporation, bylaws or other charter documents so as to adversely affect any rights of the Holder; (ii) repay, repurchase or offer to repay, repurchase or otherwise acquire shares of its Common Stock or other equity securities other than as to the Underlying Shares to the extent permitted or required under the Transaction Documents; or (iii) enter into any agreement with respect to any of the foregoing, except as may be required or permitted by the Senior Secured Financing Documents.

Section 7.              This Debenture shall not entitle the Holder to any of the rights of a stockholder of the Obligor, including without limitation, the right to vote, to receive dividends and other distributions, or to receive any notice of, or to attend, meetings of stockholders or any other proceedings of the Obligor, unless and to the extent converted into shares of Common Stock in accordance with the terms hereof

Section 8.              If this Debenture is mutilated, lost, stolen or destroyed, the Obligor shall execute and deliver, in exchange and substitution for and upon cancellation of the mutilated Debenture, or in lieu of or in substitution for a lost, stolen or destroyed Debenture, a new Debenture for the principal amount of this Debenture so mutilated, lost, stolen or destroyed but only upon receipt of evidence of such loss, theft or destruction of such Debenture, and of the ownership hereof, and indemnity, if requested, all reasonably satisfactory to the Obligor.

Section 9.              From and after the date on which all of the Senior Secured Convertible Notes have been fully paid and satisfied in accordance with their terms, (a) no indebtedness of the Obligor will be senior to this Debenture in right of payment, whether with respect to interest, damages or upon liquidation or dissolution or otherwise; and (b) without the Holder’s consent, the Obligor will not and will not permit any of its Subsidiaries to, directly or indirectly, enter into, create, incur, assume or suffer to exist any indebtedness of any kind, on or with respect to any of its property or assets now owned or hereafter acquired or any interest therein or any income or profits there from that is senior in any respect to the obligations of the Obligor under this Debenture.

Section 10.            This Debenture shall be governed by and construed in accordance with the laws of the State of New Jersey, without giving effect to conflicts of laws thereof. Each of the parties consents to the jurisdiction of the Superior Courts of the State of New Jersey sitting in Hudson County, New Jersey and the U.S. District Court for the District of New Jersey sitting in Newark, New Jersey in connection with any dispute arising under this Debenture and hereby

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waives, to the maximum extent permitted by law, any objection, including any objection based on forum non conveniens to the bringing of any such proceeding in such jurisdictions.

Section 11.            If the Obligor fails to strictly comply with the terms of this Debenture, then the Obligor shall reimburse the Holder promptly for all fees, costs and expenses, including, without limitation, attorneys’ fees and expenses incurred by the Holder in any action in connection with this Debenture, including, without limitation, those incurred: (i) during any workout, attempted workout, and/or in connection with the rendering of legal advice as to the Holder’s rights, remedies and obligations, (ii) collecting any sums which become due to the Holder, (iii) defending or prosecuting any proceeding or any counterclaim to any proceeding or appeal; or (iv) the protection, preservation or enforcement of any rights or remedies of the Holder.

Section 12.            Any waiver by the Holder of a breach of any provision of this Debenture shall not operate as or be construed to be a waiver of any other breach of such provision or of any breach of any other provision of this Debenture. The failure of the Holder to insist upon strict adherence to any term of this Debenture on one or more occasions shall not be considered a waiver or deprive that party of the right thereafter to insist upon strict adherence to that term or any other term of this Debenture. Any waiver must be in writing.

Section 13.            If any provision of this Debenture is invalid, illegal or unenforceable, the balance of this Debenture shall remain in effect, and if any provision is inapplicable to any person or circumstance, it shall nevertheless remain applicable to all other persons and circumstances. If it shall be found that any interest or other amount deemed interest due hereunder shall violate applicable laws governing usury, the applicable rate of interest due hereunder shall automatically be lowered to equal the maximum permitted rate of interest. The Obligor covenants (to the extent that it may lawfully do so) that it shall not at any time insist upon, plead, or in any manner whatsoever claim or take the benefit or advantage of, any stay, extension or usury law or other law which would prohibit or forgive the Obligor from paying all or any portion of the principal of or interest on this Debenture as contemplated herein, wherever enacted, now or at any time hereafter in force, or which may affect the covenants or the performance of this indenture, and the Obligor (to the extent it may lawfully do so) hereby expressly waives all benefits or advantage of any such law, and covenants that it will not, by resort to any such law, hinder, delay or impeded the execution of any power herein granted to the Holder, but will suffer and permit the execution of every such as though no such law has been enacted.

Section 14.            Whenever any payment or other obligation hereunder shall be due on a day other than a Business Day, such payment shall be made on the next succeeding Business Day.

Section 15.            THE PARTIES HEREBY KNOWINGLY, VOLUNTARILY AND INTENTIONALLY WAIVE THE RIGHT ANY OF THEM MAY HAVE TO A TRIAL BY JURY IN RESPECT OF ANY LITIGATION BASED HEREON OR ARISING OUT OF, UNDER OR IN CONNECTION WITH THIS DEBENTURE OR ANY TRANSACTION

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DOCUMENT OR ANY COURSE OF CONDUCT, COURSE OF DEALING, STATEMENTS (WHETHER VERBAL OR WRITTEN) OR ACTIONS OF ANY PARTY. THIS PROVISION IS A MATERIAL INDUCEMENT FOR THE PARTIES’ ACCEPTANCE OF THIS DEBENTURE.

Section 16.            Entire Agreement. This Debenture reflects the entire understanding of the Obligor and the Holder with respect to the transactions contemplated hereby and shall not be contradicted or qualified by any other agreement, oral or written, entered into before the date hereof.

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IN WITNESS WHEREOF, the Obligor has caused this Amended and Restated Secured Convertible Debenture to be duly executed by a duly authorized officer as of the date set forth above.

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EXHIBIT “A”

NOTICE OF CONVERSION

(To be executed by the Holder in order to convert the Debenture)

TO:

The undersigned hereby irrevocably elects to convert $                           of the principal amount of the above Debenture into Shares of Common Stock of Wentworth Energy, Inc., according to the conditions stated therein, as of the Conversion Date written below.

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