AMENDED AND RESTATED STOCK PURCHASE WARRANT

Exhibit 4.3

THIS WARRANT AND THE SHARES ISSUABLE UPON THE EXERCISE OF THIS WARRANT HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED. EXCEPT AS OTHERWISE SET FORTH HEREIN OR IN A SECURITIES PURCHASE AGREEMENT DATED AS OF NOVEMBER     , 2002, NEITHER THIS WARRANT NOR ANY OF SUCH SHARES MAY BE SOLD, TRANSFERRED OR ASSIGNED IN THE ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT FOR SUCH SECURITIES UNDER SAID ACT OR, AN OPINION OF COUNSEL, IN FORM, SUBSTANCE AND SCOPE, REASONABLY SATISFACTORY TO K2 INC. THAT REGISTRATION IS NOT REQUIRED UNDER SUCH ACT OR UNLESS SOLD PURSUANT TO RULE 144 UNDER SUCH ACT.

AMENDED AND RESTATED STOCK PURCHASE WARRANT

THIS CERTIFIES THAT, for value received, k1 Ventures Limited or its registered assigns, is entitled to purchase from K2 Inc., a Delaware corporation (the “Company”), at any time or from time to time during the period specified in Paragraph 2 hereof, Five Hundred Twenty Four Thousand Three Hundred Twenty Nine (524,329) fully paid and nonassessable shares of the Company’s common stock, par value $1.00 per share (the “Common Stock”), at an exercise price of $11.92 per share (the “Exercise Price”). The term “Warrant Shares,” as used herein, refers to the shares of Common Stock purchasable hereunder. The Warrant Shares and the Exercise Price are subject to adjustment as provided in Paragraph 4 hereof. The term Warrants means this Warrant and the other warrants issued pursuant to that certain Securities Purchase Agreement, dated November         , 2002, among the Company and the Buyers listed on the execution page thereof (the “Securities Purchase Agreement”).

This Warrant is subject to the following terms, provisions, and conditions:

1. Manner of Exercise; Issuance of Certificates; Payment for Shares. Subject to the provisions hereof, this Warrant may be exercised by the holder hereof, in whole or in part, by the surrender of this Warrant, together with a completed exercise agreement in the form attached hereto (the “Exercise Agreement”), to the Company during normal business hours on any business day at the Company’s principal executive offices (or such other office or agency of the Company as it may designate by notice to the holder hereof), and upon payment to the Company in cash, by certified or official bank check or by wire transfer for the account of the Company of the Exercise Price for the Warrant Shares specified in the Exercise Agreement. The Warrant

Shares so purchased shall be deemed to be issued to the holder hereof or such holder’s designee, as the record owner of such shares, as of the close of business on the date on which this Warrant shall have been surrendered, the completed Exercise Agreement shall have been delivered, and payment shall have been made for such shares as set forth above. Certificates for the Warrant Shares so purchased, representing the aggregate number of shares specified in the Exercise Agreement, shall be delivered to the holder hereof within a reasonable time, not exceeding three (3) business days, after this Warrant shall have been so exercised. The certificates so delivered shall be in such denominations as may be requested by the holder hereof and shall be registered in the name of such holder or such other name as shall be designated by such holder. If this Warrant shall have been exercised only in part, then, unless this Warrant has expired, the Company shall, at its expense, at the time of delivery of such certificates, deliver to the holder a new Warrant representing the number of shares with respect to which this Warrant shall not then have been exercised.

Notwithstanding anything in this Warrant to the contrary, in no event shall the holder of this Warrant be entitled to exercise a number of Warrants (or portions thereof) in excess of the number of Warrants (or portions thereof) upon exercise of which the sum of (i) the number of shares of Common Stock beneficially owned by the holder of this Warrant and its affiliates, including, without limitation, the shares of Common Stock issuable upon exercise of the New Warrant (other than shares of Common Stock which may be deemed beneficially owned through the ownership of the unexercised Warrants and the unexercised or unconverted portion of any other securities of the Company (excluding however the New Warrants but including the Debentures (as defined in the Securities Purchase Agreement)) subject to a limitation on conversion or exercise analogous to the limitation contained herein) and (ii) the number of shares of Common Stock issuable upon exercise of the Warrants and the New Warrants (or portions thereof) with respect to which the determination described herein is being made, would result in beneficial ownership by the holder of this Warrant and its affiliates of more than 9.9% of the outstanding shares of Common Stock. For purposes of the immediately preceding sentence, beneficial ownership shall be determined in accordance with Section 13(d) of the Securities Exchange Act of 1934, as amended, and Regulations 13D-G thereunder, except as otherwise provided in clause (i) hereof. Notwithstanding anything in this Warrant to the contrary, the restrictions on exercise of this Warrant set forth in this paragraph shall not be amended without (i) the written consent of the holder of this Warrant and the Company and (ii) the approval of the holders of a majority of the Common Stock present, or represented by proxy, and voting at any meeting called to vote on the amendment of such restriction.

As used herein the “New Warrants” means those warrants to purchase 243,260 shares of Common Stock of the Company issuable pursuant to the Stock Purchase Warrant dated as of June 4, 2003 executed by the Company for the benefit of k1 Ventures Limited, as amended, restated, supplemented or otherwise modified from time to time.

2. Period of Exercise. This Warrant is exercisable at any time or from time to time on or after the date on which this Warrant is issued and delivered pursuant to the terms of the Securities Purchase Agreement (the “Issue Date”) and before 5:00 p.m., New York City time on the fifth (5th) anniversary of the Closing Date (the “Exercise Period”).

2

3. Certain Agreements of the Company. The Company hereby covenants and agrees as follows:

(a) Shares to be Fully Paid. All Warrant Shares will, upon issuance in accordance with the terms of this Warrant, be validly issued, fully paid, and nonassessable and free from all taxes, liens, and charges with respect to the issue thereof.

(b) Reservation of Shares. During the Exercise Period, the Company shall at all times have authorized, and reserved for the purpose of issuance upon exercise of this Warrant, a sufficient number of shares of Common Stock to provide for the exercise of this Warrant.

(c) Listing. The Company shall promptly secure the listing of the shares of Common Stock issuable upon exercise of the Warrant upon each national securities exchange or automated quotation system, if any, upon which shares of Common Stock are then listed (subject to official notice of issuance upon exercise of this Warrant) and shall maintain, so long as any other shares of Common Stock shall be so listed, such listing of all shares of Common Stock from time to time issuable upon the exercise of this Warrant; and the Company shall so list on each national securities exchange or automated quotation system, as the case may be, and shall maintain such listing of, any other shares of capital stock of the Company issuable upon the exercise of this Warrant if and so long as any shares of the same class shall be listed on such national securities exchange or automated quotation system.

(d) Certain Actions Prohibited. The Company will not, by amendment of its charter or through any reorganization, transfer of assets, consolidation, merger, dissolution, issue or sale of securities, or any other voluntary action, avoid or seek to avoid the observance or performance of any of the terms to be observed or performed by it hereunder, but will at all times in good faith assist in the carrying out of all the provisions of this Warrant and in the taking of all such action as may reasonably be requested by the holder of this Warrant in order to protect the exercise privilege of the holder of this Warrant against dilution or other impairment, consistent with the tenor and purpose of this Warrant. Without limiting the generality of the foregoing, the Company (i) will not increase the par value of any shares of Common Stock receivable upon the exercise of this Warrant above the Exercise Price then in effect, and (ii) will take all such actions as may be necessary or appropriate in order that the Company may validly and legally issue fully paid and nonassessable shares of Common Stock upon the exercise of this Warrant.

(e) Successors and Assigns. This Warrant will be binding upon any entity succeeding to the Company by merger, consolidation, or acquisition of all or substantially all the Company’s assets.

4. Antidilution Provisions. During the Exercise Period, the Exercise Price and the number of Warrant Shares shall be subject to adjustment from time to time as provided in this Paragraph 4.

In the event that any adjustment of the Exercise Price as required herein results in a fraction of a cent, such Exercise Price shall be rounded up to the nearest cent.

(a) Adjustment of Exercise Price and Number of Shares upon Issuance of Common Stock. Except as otherwise provided in Paragraphs 4(c) and 4(e) hereof, if and

3

whenever on or after the Issue Date of this Warrant, the Company issues or sells, or in accordance with Paragraph 4(b) hereof is deemed to have issued or sold, any shares of Common Stock for no consideration or for a consideration per share (before deduction of reasonable expenses or commissions or underwriting discounts or allowances in connection therewith) less than the then effective Exercise Price on the date of issuance (or deemed issuance) of such Common Stock (a “Dilutive Issuance”), then immediately upon the Dilutive Issuance, the Exercise Price will be reduced to a price determined by multiplying the Exercise Price in effect immediately prior to the Dilutive Issuance by a fraction, (i) the numerator of which is an amount equal to the sum of (x) the number of shares of Common Stock Deemed Outstanding immediately prior to the Dilutive Issuance, plus (y) the quotient of the aggregate consideration, calculated as set forth in Paragraph 4(b) hereof, received by the Company upon such Dilutive Issuance divided by the Exercise Price in effect immediately prior to the Dilutive Issuance, and (ii) the denominator of which is the total number of shares of Common Stock Deemed Outstanding (as defined below) immediately after the Dilutive Issuance.

(b) Effect on Exercise Price of Certain Events. For purposes of determining the adjusted Exercise Price under Paragraph 4(a) hereof, the following will be applicable:

(i) Issuance of Rights or Options. If the Company in any manner issues or grants any warrants, rights or options, whether or not immediately exercisable, to subscribe for or to purchase Common Stock or other securities convertible into or exchangeable for Common Stock (“Convertible Securities”) (such warrants, rights and options to purchase Common Stock or Convertible Securities are hereinafter referred to as “Options”) and the price per share for which Common Stock is issuable upon the exercise of such Options is less than the Exercise Price on the date of issuance or grant of such Options, then the maximum total number of shares of Common Stock issuable upon the exercise of all such Options will, as of the date of the issuance or grant of such Options, be deemed to be outstanding and to have been issued and sold by the Company for such price per share. For purposes of the preceding sentence, the “price per share for which Common Stock is issuable upon the exercise of such Options” is determined by dividing (i) the total amount, if any, received or receivable by the Company as consideration for the issuance or granting of all such Options, plus the minimum aggregate amount of additional consideration, if any, payable to the Company upon the exercise of all such Options, plus, in the case of Convertible Securities issuable upon the exercise of such Options, the minimum aggregate amount of additional consideration payable upon the conversion or exchange thereof at the time such Convertible Securities first become convertible or exchangeable, by (ii) the maximum total number of shares of Common Stock issuable upon the exercise of all such Options (assuming full conversion of Convertible Securities, if applicable). No further adjustment to the Exercise Price will be made upon the actual issuance of such Common Stock upon the exercise of such Options or upon the conversion or exchange of Convertible Securities issuable upon exercise of such Options.

(ii) Issuance of Convertible Securities. If the Company in any manner issues or sells any Convertible Securities, whether or not immediately convertible (other than where the same are issuable upon the exercise of Options) and the price per

4

share for which Common Stock is issuable upon such conversion or exchange is less than the Exercise Price on the date of issuance of such Convertible Securities, then the maximum total number of shares of Common Stock issuable upon the conversion or exchange of all such Convertible Securities will, as of the date of the issuance of such Convertible Securities, be deemed to be outstanding and to have been issued and sold by the Company for such price per share. For the purposes of the preceding sentence, the “price per share for which Common Stock is issuable upon such conversion or exchange” is determined by dividing (i) the total amount, if any, received or receivable by the Company as consideration for the issuance or sale of all such Convertible Securities, plus the minimum aggregate amount of additional consideration, if any, payable to the Company upon the conversion or exchange thereof at the time such Convertible Securities first become convertible or exchangeable, by (ii) the maximum total number of shares of Common Stock issuable upon the conversion or exchange of all such Convertible Securities. No further adjustment to the Exercise Price will be made upon the actual issuance of such Common Stock upon conversion or exchange of such Convertible Securities.

(iii) Change in Option Price or Conversion Rate. If there is a change at any time in (i) the amount of additional consideration payable to the Company upon the exercise of any Options; (ii) the amount of additional consideration, if any, payable to the Company upon the conversion or exchange of any Convertible Securities; or (iii) the rate at which any Convertible Securities are convertible into or exchangeable for Common Stock (other than under or by reason of provisions designed to protect against dilution), the Exercise Price in effect at the time of such change will be readjusted to the Exercise Price which would have been in effect at such time had such Options or Convertible Securities still outstanding provided for such changed additional consideration or changed conversion rate, as the case may be, at the time initially granted, issued or sold.

(iv) Treatment of Expired Options and Unexercised Convertible Securities. If, in any case, the total number of shares of Common Stock issuable upon exercise of any Option or upon conversion or exchange of any Convertible Securities is not, in fact, issued and the rights to exercise such Option or to convert or exchange such Convertible Securities shall have expired or terminated, the Exercise Price then in effect will be readjusted to the Exercise Price which would have been in effect at the time of such expiration or termination had such Option or Convertible Securities, to the extent outstanding immediately prior to such expiration or termination (other than in respect of the actual number of shares of Common Stock issued upon exercise or conversion thereof), never been issued.

(v) Calculation of Consideration Received. If any Common Stock, Options or Convertible Securities are issued, granted or sold for cash, the consideration received therefor for purposes of this Warrant will be the amount received by the Company therefor, before deduction of reasonable commissions, underwriting discounts or allowances or other reasonable expenses paid or incurred by the Company in connection with such issuance, grant or sale. In case any Common Stock, Options or Convertible Securities are issued or sold for a consideration part or all of which shall be

5

other than cash, the amount of the consideration other than cash received by the Company will be the fair value of such consideration, except where such consideration consists of securities, in which case the amount of consideration received by the Company will be the Market Price thereof as of the date of receipt. In case any Common Stock, Options or Convertible Securities are issued in connection with any acquisition, merger or consolidation in which the Company is the surviving corporation, the amount of consideration therefor will be deemed to be the fair value of such portion of the net assets and business of the non-surviving corporation as is attributable to such Common Stock, Options or Convertible Securities, as the case may be. The fair value of any consideration other than cash or securities will be determined in good faith by the Board of Directors of the Company and set forth in a resolution.

(vi) Exceptions to Adjustment of Exercise Price. No adjustment to the Exercise Price will be made (i) upon the exercise of any warrants, options or convertible securities granted, issued and outstanding on the date of issuance of this Warrant; (ii) upon the grant or exercise of any stock or options which may hereafter be granted or exercised under any stock option plan, restricted stock plan or employee benefit plan of the Company now existing or to be implemented in the future, so long as the issuance of such stock or options is approved by a majority of the independent members of the Board of Directors of the Company or a majority of the members of a committee of independent directors established for such purpose; (iii) upon the exercise of the Warrants; (iv) upon the issuance or conversion of the Debentures; (v) upon a sale pursuant to a bona fide firm commitment underwritten public offering of Common Stock by the Company (not including a continuous offering pursuant to Rule 415 under the Securities Act); (vi) upon sales in an aggregate amount not exceeding 538,262 shares (subject to adjustment for stock splits, stock dividends, stock combination and similar transactions); (vii) upon securities issued by the Company in connection with an acquisition of a business, operating assets or a person; (viii) securities issued to any strategic investors, vendors, financial institutions or other lenders in connection with commercial credit arrangements and similar financings, lessors, customers or suppliers, lease or similar arrangements the primary purpose of which is not to raise equity capital; or (ix) upon the issuance or exercise of the New Warrant.

(c) Subdivision or Combination of Common Stock. If the Company at any time subdivides (by any stock split, stock dividend, recapitalization, reorganization, reclassification or otherwise) the shares of Common Stock acquirable hereunder into a greater number of shares, then, after the date of record for effecting such subdivision, the Exercise Price in effect immediately prior to such subdivision will be proportionately reduced. If the Company at any time combines (by reverse stock split, recapitalization, reorganization, reclassification or otherwise) the shares of Common Stock acquirable hereunder into a smaller number of shares, then, after the date of record for effecting such combination, the Exercise Price in effect immediately prior to such combination will be proportionately increased.

(d) Adjustment in Number of Shares. Upon each adjustment of the Exercise Price pursuant to the provisions of this Paragraph 4, the number of shares of Common Stock issuable upon exercise of this Warrant shall be adjusted by multiplying a number equal to the Exercise Price in effect immediately prior to such adjustment by the number of shares of

6

Common Stock issuable upon exercise of this Warrant immediately prior to such adjustment and dividing the product so obtained by the adjusted Exercise Price.

(e) Consolidation, Merger or Sale. In case of any consolidation of the Company with, or merger of the Company into any other corporation, or in case of any sale or conveyance of all or substantially all of the assets of the Company other than in connection with a plan of complete liquidation of the Company, adequate provision will be made whereby the holder of this Warrant will have the right to acquire and receive upon exercise of this Warrant in lieu of the shares of Common Stock immediately theretofore acquirable upon the exercise of this Warrant, such shares of stock, securities or assets as may be issued or payable with respect to or in exchange for the number of shares of Common Stock immediately theretofore acquirable and receivable upon exercise of this Warrant had such consolidation, merger or sale or conveyance not taken place. In any such case, the Company will make appropriate provision to insure that the provisions of this Paragraph 4 hereof will thereafter be applicable as nearly as may be in relation to any shares of stock or securities thereafter deliverable upon the exercise of this Warrant.

(f) Notice of Adjustment. Upon the occurrence of any event which requires any adjustment of the Exercise Price, then, and in each such case, the Company shall give notice thereof to the holder of this Warrant, which notice shall state the Exercise Price resulting from such adjustment and the increase or decrease in the number of Warrant Shares purchasable at such price upon exercise, setting forth in reasonable detail the method of calculation and the facts upon which such calculation is based. Such calculation shall be certified by the chief financial officer of the Company.

(g) Minimum Adjustment of Exercise Price. No adjustment of the Exercise Price shall be made in an amount of less than 1% of the Exercise Price in effect at the time such adjustment is otherwise required to be made, but any such lesser adjustment shall be carried forward and shall be made at the time and together with the next subsequent adjustment which, together with any adjustments so carried forward, shall amount to not less than 1% of such Exercise Price.

(h) No Fractional Shares. No fractional shares of Common Stock are to be issued upon the exercise of this Warrant. If the exercise of this Warrant would result in a fractional share of Common Stock, such fractional share shall be disregarded and the number of shares of Common Stock issuable upon exercise of the Warrant shall be the next higher number of shares.

(i) Other Notices. In case at any time:

(i) the Company shall declare any dividend upon the Common Stock payable in shares of stock of any class or make any other distribution (including dividends or distributions payable in cash out of retained earnings) to the holders of the Common Stock;

(ii) the Company shall offer for subscription pro rata to the holders of the Common Stock any additional shares of stock of any class or other rights;

7

(iii) there shall be any capital reorganization of the Company, or reclassification of the Common Stock, or consolidation or merger of the Company with or into, or sale of all or substantially all its assets to, another corporation or entity; or

(iv) there shall be a voluntary or involuntary dissolution, liquidation or winding-up of the Company;

then, in each such case, the Company shall give to the holder of this Warrant (a) notice of the date on which the books of the Company shall close or a record shall be taken for determining the holders of Common Stock entitled to receive any such dividend, distribution, or subscription rights or for determining the holders of Common Stock entitled to vote in respect of any such reorganization, reclassification, consolidation, merger, sale, dissolution, liquidation or winding-up and (b) in the case of any such reorganization, reclassification, consolidation, merger, sale, dissolution, liquidation or winding-up, notice of the date (or, if not then known, a reasonable approximation thereof by the Company) when the same shall take place. Such notice shall also specify the date on which the holders of Common Stock shall be entitled to receive such dividend, distribution, or subscription rights or to exchange their Common Stock for stock or other securities or property deliverable upon such reorganization, reclassification, consolidation, merger, sale, dissolution, liquidation, or winding-up, as the case may be. Such notice shall be given at least 30 days prior to the record date or the date on which the Company’s books are closed in respect thereto. Failure to give any such notice or any defect therein shall not affect the validity of the proceedings referred to in clauses (i), (ii), (iii) and (iv) above.

(j) Certain Definitions.

(i) “Common Stock Deemed Outstanding” shall mean the number of shares of Common Stock actually outstanding (not including shares of Common Stock held in the treasury of the Company), plus (x) pursuant to Paragraph 4(b)(i) hereof, the maximum total number of shares of Common Stock issuable upon the exercise of Options, as of the date of such issuance or grant of such Options, if any, and (y) pursuant to Paragraph 4(b)(ii) hereof, the maximum total number of shares of Common Stock issuable upon conversion or exchange of Convertible Securities, as of the date of issuance of such Convertible Securities, if any.

(ii) “Market Price,” as of any date, (i) means the average of the last reported sale prices for the shares of Common Stock on the New York Stock Exchange (the “NYSE”) for the five (5) trading days immediately preceding such date as reported by Bloomberg Financial Markets or an equivalent reliable reporting service mutually acceptable to and hereafter designated by the holder of this Warrant and the Company (“Bloomberg”), or (ii) if NYSE is not the principal trading market for the shares of Common Stock, the average of the last reported sale prices on the principal trading market for the Common Stock during the same period as reported by Bloomberg, or (iii) if market value cannot be calculated as of such date on any of the foregoing bases, the Market Price shall be the fair market value as reasonably determined in good faith by the Board of Directors of the Company and set forth in a resolution. The manner of determining the Market Price of the Common Stock set forth in the foregoing definition

8

shall apply with respect to any other security in respect of which a determination as to market value must be made hereunder.

(iii) “Common Stock,” for purposes of this Paragraph 4, includes the Common Stock, par value $1.00 per share, and any additional class of stock of the Company having no preference as to dividends or distributions on liquidation, provided that the shares purchasable pursuant to this Warrant shall include only shares of Common Stock, par value $1.00 per share, in respect of which this Warrant is exercisable, or shares resulting from any subdivision or combination of such Common Stock, or in the case of any reorganization, reclassification, consolidation, merger, or sale of the character referred to in Paragraph 4(e) hereof, the stock or other securities or property provided for in such Paragraph.

5. Issue Tax. The issuance of certificates for Warrant Shares upon the exercise of this Warrant shall be made without charge to the holder of this Warrant or such shares for any issuance tax or other costs in respect thereof, provided that the Company shall not be required to pay any tax which may be payable in respect of any transfer involved in the issuance and delivery of any certificate in a name other than the holder of this Warrant.

6. No Rights or Liabilities as a Shareholder. This Warrant shall not entitle the holder hereof to any voting rights or other rights as a shareholder of the Company. No provision of this Warrant, in the absence of affirmative action by the holder hereof to purchase Warrant Shares, and no mere enumeration herein of the rights or privileges of the holder hereof, shall give rise to any liability of such holder for the Exercise Price or as a shareholder of the Company, whether such liability is asserted by the Company or by creditors of the Company.

7. Transfer, Exchange, and Replacement of Warrant.

(a) Restriction on Transfer. This Warrant and the rights granted to the holder hereof are transferable, in whole or in part, upon surrender of this Warrant, together with a properly executed assignment in the form attached hereto, at the office or agency of the Company referred to in Paragraph 7(e) below, provided, however, that any transfer or assignment shall be subject to the conditions set forth in Paragraph 7(f) hereof and to the applicable provisions of the Securities Purchase Agreement. Until due presentment for registration of transfer on the books of the Company, the Company may treat the registered holder hereof as the owner and holder hereof for all purposes, and the Company shall not be affected by any notice to the contrary. Notwithstanding anything to the contrary contained herein, the registration rights described in Paragraph 8 are assignable only in accordance with the provisions of that certain Registration Rights Agreement, dated as of February 14, 2003, by and among the Company and the other signatories thereto (as the same may be amended, modified or restated, the “Registration Rights Agreement”).

(b) Warrant Exchangeable for Different Denominations. This Warrant is exchangeable, upon the surrender hereof by the holder hereof at the office or agency of the Company referred to in Paragraph 7(e) below, for new Warrants of like tenor representing in the aggregate the right to purchase the number of shares of Common Stock which may be purchased

9

hereunder, each of such new Warrants to represent the right to purchase such number of shares as shall be designated by the holder hereof at the time of such surrender.

(c) Replacement of Warrant. Upon receipt of evidence reasonably satisfactory to the Company of the loss, theft, destruction, or mutilation of this Warrant and, in the case of any such loss, theft, or destruction, upon delivery of an indemnity agreement reasonably satisfactory in form and amount to the Company, or, in the case of any such mutilation, upon surrender and cancellation of this Warrant, the Company, at its expense, will execute and deliver, in lieu thereof, a new Warrant of like tenor.

(d) Cancellation; Payment of Expenses. Upon the surrender of this Warrant in connection with any transfer, exchange, or replacement as provided in this Paragraph 7, this Warrant shall be promptly canceled by the Company. The Company shall pay all taxes (other than securities transfer taxes) and all other expenses (other than legal expenses, if any, incurred by the Holder or transferees) and charges payable in connection with the preparation, execution, and delivery of Warrants pursuant to this Paragraph 7.

(e) Register. The Company shall maintain, at its principal executive offices (or such other office or agency of the Company as it may designate by notice to the holder hereof), a register for this Warrant, in which the Company shall record the name and address of the person in whose name this Warrant has been issued, as well as the name and address of each transferee and each prior owner of this Warrant.

(f) Exercise or Transfer Without Registration. If, at the time of the surrender of this Warrant in connection with any exercise, transfer, or exchange of this Warrant, this Warrant (or, in the case of any exercise, the Warrant Shares issuable hereunder), shall not be registered under the Securities Act and under applicable state securities or blue sky laws, the Company may require, as a condition of allowing such exercise, transfer, or exchange, (i) that the holder or transferee of this Warrant, as the case may be, furnish to the Company a written opinion of counsel, which opinion and counsel are acceptable to the Company, to the effect that such exercise, transfer, or exchange may be made without registration under said Act and under applicable state securities or blue sky laws, (ii) that the holder or transferee execute and deliver to the Company an investment letter in form and substance acceptable to the Company and (iii) that the transferee be an “accredited investor” as defined in Rule 501(a) promulgated under the Securities Act; provided that no such opinion, letter or status as an “accredited investor” shall be required in connection with a transfer pursuant to Rule 144 under the Securities Act. The first holder of this Warrant, by taking and holding the same, represents to the Company that such holder is acquiring this Warrant for investment and not with a view to the distribution thereof.

8. Registration Rights. The initial holder of this Warrant (and certain assignees thereof) is entitled to the benefit of such registration rights in respect of the Warrant Shares as are set forth in Section 2 of the Registration Rights Agreement.

9. Notices. All notices, requests, and other communications required or permitted to be given or delivered hereunder to the holder of this Warrant shall be in writing, and shall be personally delivered, or shall be sent by certified or registered mail or by recognized overnight mail courier, postage prepaid and addressed, to such holder at the address shown for such holder

10

on the books of the Company, or at such other address as shall have been furnished to the Company by notice from such holder. All notices, requests, and other communications required or permitted to be given or delivered hereunder to the Company shall be in writing, and shall be personally delivered, or shall be sent by certified or registered mail or by recognized overnight mail courier, postage prepaid and addressed, to the office of the Company at 2051 Palomar Airport Road, Carlsbad, California 92009, Attention: General Counsel, or at such other address as shall have been furnished to the holder of this Warrant by notice from the Company. Any such notice, request, or other communication may be sent by facsimile, but shall in such case be subsequently confirmed by a writing personally delivered or sent by certified or registered mail or by recognized overnight mail courier as provided above. All notices, requests, and other communications shall be deemed to have been given either at the time of the receipt thereof by the person entitled to receive such notice at the address of such person for purposes of this Paragraph 9, or, if mailed by registered or certified mail or with a recognized overnight mail courier upon deposit with the United States Post Office or such overnight mail courier, if postage is prepaid and the mailing is properly addressed, as the case may be.

10. Governing Law. THE CORPORATE LAWS OF THE STATE OF DELAWARE SHALL GOVERN ALL ISSUES CONCERNING THE RELATIVE RIGHTS OF THE COMPANY AND ITS STOCKHOLDERS. ALL OTHER QUESTIONS UNDER THIS WARRANT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK APPLICABLE TO AGREEMENTS MADE AND TO BE PERFORMED IN THE STATE OF NEW YORK (WITHOUT REGARD TO PRINCIPLES OF CONFLICT OF LAWS). BOTH PARTIES IRREVOCABLY CONSENT TO THE NON-EXCLUSIVE JURISDICTION OF THE UNITED STATES FEDERAL COURTS AND THE STATE COURTS LOCATED IN THE CITY OF NEW YORK, BOROUGH OF MANHATTAN, WITH RESPECT TO ANY SUIT OR PROCEEDING BASED ON OR ARISING UNDER THIS STOCK PURCHASE WARRANT, THE AGREEMENTS ENTERED INTO IN CONNECTION HEREWITH OR THE TRANSACTIONS CONTEMPLATED HEREBY OR THEREBY AND IRREVOCABLY AGREE THAT ALL CLAIMS IN RESPECT OF SUCH SUIT OR PROCEEDING MAY BE DETERMINED IN SUCH COURTS. BOTH PARTIES IRREVOCABLY WAIVE THE DEFENSE OF AN INCONVENIENT FORUM TO THE MAINTENANCE OF SUCH SUIT OR PROCEEDING. BOTH PARTIES FURTHER AGREE THAT SERVICE OF PROCESS UPON A PARTY MAILED BY FIRST CLASS MAIL SHALL BE DEEMED IN EVERY RESPECT EFFECTIVE SERVICE OF PROCESS UPON THE PARTY IN ANY SUCH SUIT OR PROCEEDING. NOTHING HEREIN SHALL AFFECT EITHER PARTY’S RIGHT TO SERVE PROCESS IN ANY OTHER MANNER PERMITTED BY LAW. BOTH PARTIES AGREE THAT A FINAL NON-APPEALABLE JUDGMENT IN ANY SUCH SUIT OR PROCEEDING SHALL BE CONCLUSIVE AND MAY BE ENFORCED IN OTHER JURISDICTIONS BY SUIT ON SUCH JUDGMENT OR IN ANY OTHER LAWFUL MANNER.

11. Miscellaneous.

(a) Amendments. This Warrant and any provision hereof may only be amended by an instrument in writing signed by the Company and the holder hereof.

11

(b) Descriptive Headings. The descriptive headings of the several paragraphs of this Warrant are inserted for purposes of reference only, and shall not affect the meaning or construction of any of the provisions hereof.

(c) Remedies. The Company acknowledges that a breach by it of its obligations hereunder will cause irreparable harm to the holder of this Warrant by vitiating the intent and purpose of the transactions contemplated hereby. Accordingly, the Company acknowledges that the remedy at law for a breach of its obligations under this Warrant will be inadequate and agrees, in the event of a breach or a threatened breach in writing by the Company of the provisions of this Warrant, that the holder of this Warrant shall be entitled, in addition to all other available remedies in law or in equity, to an injunction or injunctions to prevent or cure any breaches of the provisions of this Agreement and to enforce specifically the terms and provisions of this Warrant, without the necessity of showing economic loss and without any bond or other security being required.

(d) Board Determinations. In the event the Board of Directors of the Company exercises its obligation to determine the fair market value of the Common Stock in accordance with the terms of this Warrant, the Company shall provide to the holder hereof together with a copy of resolution setting forth the Board of Directors’ good faith determination of the fair market value of such Common Stock a certificate setting forth in reasonable detail the process by which the Board of Directors of the Company made its determination.

(e) Effect on Original Warrant. This Warrant amends and restates the Company’s Stock Purchase Warrant dated February 14, 2003 (the “Original Warrant”) concerning the right to purchase 524,329 shares of Common Stock by the Holder; and the Company and the Holder hereby agree that the execution and delivery of this Warrant shall not constitute or effect or be deemed to constitute or effect and extinguishment or cancellation of the Original Warrant.

[REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK]

12

IN WITNESS WHEREOF, the Company has caused this Warrant to be signed by its duly authorized officer.

Dated as of June 4, 2003

13

FORM OF EXERCISE AGREEMENT

Dated:                          ,         

To:                                 

The undersigned, pursuant to the provisions set forth in the within Warrant, hereby agrees to purchase              shares of Common Stock covered by such Warrant, and makes payment herewith in full therefor at the price per share provided by such Warrant in cash or by certified or official bank check in the amount of. Please issue a certificate or certificates for such shares of Common Stock in the name of and pay any cash for any fractional share to:

and, if said number of shares of Common Stock shall not be all the shares purchasable under the within Warrant, a new Warrant is to be issued in the name of said undersigned covering the balance of the shares purchasable thereunder less any fraction of a share paid in cash.

FORM OF ASSIGNMENT

FOR VALUE RECEIVED, the undersigned hereby sells, assigns, and transfers all the rights of the undersigned under the within Warrant, with respect to the number of shares of Common Stock covered thereby set forth hereinbelow, to:

, and hereby irrevocably constitutes and appoints                                                       as agent and attorney-in-fact to transfer said Warrant on the books of the within-named corporation, with full power of substitution in the premises.

Dated:                          , 200_

In the presence of: