CHANGE OF CONTROL EXECUTIVE SEVERANCE AGREEMENT

Exhibit 10.23

CHANGE OF CONTROL EXECUTIVE SEVERANCE AGREEMENT

THIS CHANGE OF CONTROL EXECUTIVE SEVERANCE AGREEMENT (“Agreement”) is entered into as of the 19th day of January, 2004, by and between COMMERCIAL FEDERAL CORPORATION, a Nebraska corporation (the “Corporation”), and its wholly-owned subsidiary, COMMERCIAL FEDERAL BANK, A FEDERAL SAVINGS BANK (the “Bank”), referred to collectively as the “Employer,” and William A. Fitzgerald (the “Executive”).

A. The Executive is a key member of the management of the Employer. It is in the best interests of the Corporation, its shareholders, and the Bank to provide an inducement to the Executive to remain in the service of the Employer in the event of any proposed or anticipated Change of Control of the Employer as defined herein, as well as to facilitate an orderly transition in the event of a Change of Control.

B. The Employer wishes to provide economic security for the Executive in the event of a Change of Control.

C. The following provisions have been approved by the Boards of Directors of the Corporation and the Bank (the “Boards”), and the following Sections shall apply in the event of a Change of Control:

a. The acquisition by any individual, entity or group (within the meaning of Section 13(d)(3) or 14(d)(2) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”)) (a “Person”) of beneficial ownership (within the meaning of Rule 13d-3 promulgated under the Exchange Act) of 49% or more of either (A) the then-outstanding shares of common stock of the Corporation (the “Outstanding Corporation Common Stock”) or (B) the combined voting power of the then-outstanding voting securities of the Corporation entitled to vote generally in the election of directors (the “Outstanding Corporation Voting Securities”); provided, however, that, for purposes of this Section 2(a), the following acquisitions shall not constitute a Change of Control Event: (i) any acquisition directly from the Corporation, (ii) any acquisition by the Corporation, (iii) any acquisition by any employee benefit plan (or related trust) sponsored or maintained by the Corporation or any of its affiliated companies or (iv) any acquisition by any corporation pursuant to a transaction that complies with Sections 2(c)(i), 2(c)(ii) and 2(c)(iii).

b. Individuals who, as of the date hereof, constitute the Board of the Corporation (the “Incumbent Board”) cease for any reason to constitute at least a majority of the Board of the Corporation; provided, however, that any individual becoming a director subsequent to the date hereof whose election, or nomination for election by the Corporation’s stockholders, was approved by a vote of at least a majority of the directors then comprising the Incumbent Board

shall be considered as though such individual were a member of the Incumbent Board, but excluding, for this purpose, any such individual whose initial assumption of office occurs as a result of an actual or threatened election contest with respect to the election or removal of directors or other actual or threatened solicitation of proxies or consents by or on behalf of a Person other than the Board of the Corporation.

c. Consummation of a reorganization, merger, consolidation or a sale or other disposition of all or substantially all of the assets of the Corporation (each, a “Business Combination”), in each case unless, following such Business Combination, (i) all or substantially all of the individuals and entities that were the beneficial owners of the Outstanding Corporation Common Stock and the Outstanding Corporation Voting Securities immediately prior to such Business Combination beneficially own, directly or indirectly, more than 50% of the then-outstanding shares of common stock and the combined voting power of the then-outstanding voting securities entitled to vote generally in the election of directors, as the case may be, of the corporation resulting from such Business Combination (including, without limitation, a corporation that, as a result of such transaction, owns the Corporation or all or substantially all of the Corporation’s assets either directly or through one or more subsidiaries) in substantially the same proportions as their ownership immediately prior to such Business Combination of the Outstanding Corporation Common Stock and the Outstanding Corporation Voting Securities, as the case may be, (ii) no Person (excluding any corporation resulting from such Business Combination or any employee benefit plan (or related trust) of the Corporation or such corporation resulting from such Business Combination) beneficially owns, directly or indirectly, 49% or more of, respectively, the then-outstanding shares of common stock of the corporation resulting from such Business Combination or the combined voting power of the then-outstanding voting securities of such corporation, except to the extent that such ownership existed prior to the Business Combination, and (iii) at least a majority of the members of the board of directors of the corporation resulting from such Business Combination were members of the Incumbent Board at the time of the execution of the initial agreement or of the action of the Board providing for such Business Combination.

d. Approval by the stockholders of the Corporation of a complete liquidation or dissolution of the Corporation.

e. The occurrence of any event that would constitute a Change of Control Event were the term “Bank” substituted for the term “Corporation” in every instance where the term “Corporation” appears in Sections 2(a-d) hereof, other than an event after which the Corporation and its affiliates in the aggregate continue to hold, directly or indirectly, at least a majority of both the then-outstanding shares of common stock of the Bank and the combined voting power of the then-outstanding voting securities of the Bank entitled to vote generally in the election of directors (unless such event is approval by the stockholders of the Bank of a complete liquidation or dissolution of the Bank, which shall be considered a Change of Control Event in all cases).

3. Constructive Involuntary Termination. A Constructive Involuntary Termination is deemed to have occurred if, in anticipation of a Change of Control Event, or during the three-year period after such an event has occurred, any of the following occurs:

a. The assignment to the Executive of any duties inconsistent in any respect with the Executive’s position (including status, offices, titles and reporting requirements), authority, duties or responsibilities, or any other action by the Employer that results in a diminution in such position, authority, duties or responsibilities, excluding for this purpose an isolated,

insubstantial and inadvertent action that is not taken in bad faith and that is remedied by the Employer promptly after receipt of notice thereof given by the Executive.

b. The Executive’s compensation level is reduced.

c. The level of the Executive’s participation in incentive compensation is reduced or eliminated.

d. The Executive’s benefit coverage or perquisites are reduced or eliminated, except to the extent such reduction or elimination applies to all other employees.

e. The Executive’s office location is changed to a location greater than fifty (50) miles from the location of the Executive’s office at the time of the Change of Control Event.

f. Any purported termination by the Employer of the Executive’s employment other than as expressly permitted by this Agreement; or

g. Any failure by the Employer to comply with and satisfy Section 9 of this Agreement.

For purposes of this Section 3, any good faith determination of Constructive Involuntary Termination made by the Executive shall be conclusive. The Executive’s mental or physical incapacity following the occurrence of an event described above in clauses (a) through (g) shall not affect the Executive’s ability to terminate employment for Constructive Involuntary Termination.

Anything in this Agreement to the contrary notwithstanding, a termination by the Executive for any reason during the 30-day period immediately following the first anniversary of the Change of Control Event (the “Window Period”) shall be deemed to be a Constructive Involuntary Termination for all purposes of this Agreement.

4. Termination for Cause, Executive’s Breach. The benefits provided herein shall not be due in the event the Executive’s employment is terminated for Cause or if the Executive breaches any obligation in Section 8. The term “Cause” shall mean (a) the willful and continued failure of the Executive to perform substantially the Executive’s duties with the Employer, after a written demand for substantial performance is delivered to the Executive by either of the Boards or by the Chief Executive Officer of the Corporation or the Bank that specifically identifies the manner in which such Board or such Chief Executive Officer believes that the Executive has not substantially performed the Executive’s duties, and (b) the willful engaging by the Executive in illegal conduct or gross misconduct that is materially and demonstrably injurious to the Employer. For purposes of this Section 4, no act, or failure to act, on the part of the Executive shall be considered “willful” unless it is done, or omitted to be done, by the Executive in bad faith or without reasonable belief that the Executive’s action or omission was in the best interests of the Employer. Any act, or failure to act, based upon authority given pursuant to a resolution duly adopted by either of the Boards or upon the instructions of the Chief Executive Officer of the Corporation or the Bank, or a senior officer of the Corporation or the Bank or based upon the advice of counsel for the Employer shall be conclusively presumed to be done, or omitted to be done, by the Executive in good faith and in the best interests of the Employer. The cessation of employment of the Executive shall not be deemed to be for Cause unless and until there shall have been delivered to the Executive a copy of a resolution duly adopted by the affirmative vote of not less than three-quarters of the entire membership of either Board at a meeting of such Board called and held for such purpose (after reasonable notice is provided to the Executive and the Executive is given an opportunity, together with counsel for the Executive, to be heard before the Board), finding that, in the good faith opinion of such Board, the Executive is guilty of the conduct

described in this Section 4 constituting basis for termination for Cause, and specifying the particulars thereof in detail.

5. Voluntary Termination. The benefits provided herein shall not be due in the event of a voluntary termination. A voluntary termination will have occurred if the Executive resigns from the successor corporation after a Change of Control under conditions other than as constitute a Constructive Involuntary Termination.

6. Regulatory Provisions Applicable Only to the Bank.

a. If the Executive is suspended and/or temporarily prohibited from participating in the conduct of the Bank’s affairs by a notice served under Section 8(e)(3) or (g)(1) of the Federal Deposit Insurance Act (12 U.S.C. § 1818(e)(3) and (g)(1)), the Bank’s obligations under this Agreement shall be suspended as of the date of service unless stayed by appropriate proceedings. If the charges in the notice are dismissed, the Bank may in its discretion (i) pay the Executive all or part of the compensation withheld while its contract obligations were suspended; and (ii) reinstate (in whole or in part) any of its obligations which were suspended.

b. If the Executive is removed and/or permanently prohibited from participating in the conduct of the Bank’s affairs by an order issued under Section 8(e)(4) or (g)(1) of the Federal Deposit Insurance Act (12 U.S.C. § 1818(e)(4) or (g)(1)), all obligations of the Bank under this Agreement shall terminate as of the effective date of the order, but vested rights of the contracting parties shall not be affected.

c. If the Bank is in default (as defined in Section 3(x)(1) of the Federal Deposit Insurance Act), all obligations of the Bank under this Agreement shall terminate as of the date of default, but this paragraph shall not affect any vested rights of the contracting parties.

d. All obligations of the Bank under this Agreement shall be terminated, except to the extent determined that continuation of this Agreement is necessary for the continued operation of the Bank:

i. At the time the Federal Deposit Insurance Corporation (“FDIC”) enters into an agreement to provide assistance to or on behalf of the Bank under the authority contained in Section 13(c) of the Federal Deposit Insurance Act; or

ii. At the time the FDIC approves a supervisory merger to resolve problems related to operation of the Bank or when the Bank is determined by the Director to be in an unsafe or unsound condition.

Any rights of the parties that have already vested, however, shall not be affected by such action.

7. Severance Award. If, in anticipation of a Change of Control, or during the three-year period after a Change of Control Event has occurred, the Executive’s employment is terminated other than for Cause, or a Constructive Involuntary Termination occurs, then, so long as Executive is not in breach of Section 8 below, the following provisions shall apply:

a. The Executive will continue to receive, in equal monthly payments due on each monthly anniversary of the Executive’s date of termination, the base salary and all commissions and bonuses (including short- and long-term incentive programs and stock options granted pursuant to the Corporation’s executive incentive plan) in effect at the time of the involuntary

termination for a period of 35.88 months from the date of termination reduced by the number of months the Executive remained in the employ of the Employer after a Change of Control Event occurred. For purposes of this paragraph, commissions shall be determined by computing the average monthly commission earned by the Executive for the twenty four (24) months immediately preceding the month in which such termination of employment occurs, and bonuses shall be determined by dividing the average of the Executive’s two most recent annual bonuses for full fiscal years (or, if the Executive has only received one such bonus, the amount of such bonus, or, if the executive has received no such bonuses, the amount of the Executive’s target bonus) by 12. Any payments made by the Bank to the Executive pursuant to this Agreement, or otherwise, are subject to and conditioned upon their compliance with 12 U.S.C. § 1828(K) and any regulation promulgated thereunder.

b. During the period of months for which the Executive receives compensation under the preceding paragraph, the Executive will also continue to participate in any health, disability, and life insurance plan to the same extent as if the Executive were an employee of the Employer or any successor corporation. In the event that the Executive’s participation in any of these plans is prohibited, the Employer or successor corporation, at its sole expense, shall provide the Executive with benefits substantially similar to those which the Executive is entitled to receive under any such plan. The Executive shall remain responsible for that portion of the costs of such plans for which the Executive was responsible prior to termination.

c. The Executive will also continue to participate until the end of such period in any perquisite program (auto, country club, dining club, physical, tax planning, etc.) of the Employer or any successor corporation, to the same extent as if the Executive were an employee of the successor corporation. In the event the providing of any such program is not possible, the Employer shall arrange, at its sole cost, to provide an equivalent benefit. The Employer may elect to substitute a cash payment equivalent to the projected value of any perquisite over the transition period.

d. It is not the intent of the parties to this Agreement that payment hereunder will constitute a “parachute payment” as defined in Section 280G of the Internal Revenue Code of 1986, as amended (the “Code”) (“Section 280G”). Accordingly, all benefits and payments pursuant to this Section 7 shall be reduced, if necessary, to the largest aggregate amount that will result in no portion thereof being subject to federal excise tax or being nondeductible to the Employer for federal income tax purposes under Sections 280G or 4999 of the Code. The Executive will determine which payments or benefits are to be reduced, if necessary to conform to this provision.

e. For the avoidance of doubt, termination of this Agreement pursuant to Section 1 upon termination of the Executive’s employment shall in no way limit the obligation of the Employer to provide post-termination payments and benefits pursuant to this Section 7 if such termination of employment occurred under circumstances entitling the Executive to such payments and benefits.

8. Confidentiality. The Executive shall hold in a fiduciary capacity, for the benefit of the Corporation, the Bank and any of their affiliated companies, all secret or confidential information, knowledge or data relating to any of them and their respective businesses and customers which shall have been obtained by the Executive during his or her employment. After the termination of the Executive’s employment the Executive shall not, without the express written consent of the Corporation and the Bank, communicate or divulge any such information, knowledge or data to, or employ the same for the benefit of, any other person or party. The provisions of this Section 8 shall survive any termination of this Agreement and are supplemental to, and not in limitation of, any other

obligation Executive may have under any other agreement, express or implied, or at law, with respect to the subject matter hereof.

9. Successors and Assigns. This Agreement shall be binding upon and inure to the benefit of the successors of the Corporation and the Bank.

The Executive shall have no right to assign, pledge, or otherwise dispose of or transfer any interest in this Agreement, whether directly or indirectly, or in whole or in part.

10. Joint and Several Liability. It is the intent of the parties hereto that the liability of the Corporation and the Bank hereunder be joint and several. If either such party shall be prohibited for any reason from fulfilling the terms hereof, the other such party shall nevertheless be and remain fully liable.

11. Severability. In the event that any portion of this Agreement is held to be invalid or unenforceable for any reason, it is hereby agreed that invalidity or unenforceability shall not affect the other portions of this Agreement and that the remaining covenants, terms, and conditions shall remain in full force and effect and any court of competent jurisdiction may so modify the objectionable provisions as to make it valid and enforceable.

12. Governing Law; Amendment. This Agreement shall be construed in accordance with the laws of the State of Nebraska, and supersedes any existing Change of Control agreement between the parties hereto. This Agreement may not be amended, modified, or terminated other than by a written agreement executed by the parties hereto or their respective successors and legal representatives.

IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the day and year first above written.

AMENDMENT TO CHANGE OF CONTROL EXECUTIVE SEVERANCE

AGREEMENT

The Change of Control Executive Severance Agreement (the “Agreement”) entered into as of the 19^th day of January 2004, by and between Commercial Federal Corporation (the “Corporation”), Commercial Federal Bank, and William A. Fitzgerald (the “Executive”), is hereby amended pursuant to this amendment (the “Amendment”) effective as of the date hereof.

AMENDMENT

1. Section 7(d) shall be deleted in its entirety and Section 7(e) shall be changed to Section 7(d).

2. The Agreement is hereby amended by adding the following new Section 13 to the Agreement:

“13. Certain Additional Payments by the Corporation.

(a) Anything in this Agreement to the contrary notwithstanding and except as set forth below, in the event it shall be determined that any Payment would be subject to the Excise Tax, then the Executive shall be entitled to receive an additional payment (the “Gross-Up Payment”) in an amount such that, after payment by the Executive of all taxes (and any interest or penalties imposed with respect to such taxes), including, without limitation, any income taxes (and any interest and penalties imposed with respect thereto) and Excise Tax imposed upon the Gross-Up Payment, the Executive retains an amount of the Gross-Up Payment equal to the Excise Tax imposed upon the Payments. The Corporation’s obligation to make Gross-Up Payments under this Section 13 shall not be conditioned upon the Executive’s termination of employment.

(b) Subject to the provisions of Section 13(c), all determinations required to be made under this Section 13, including whether and when a Gross-Up Payment is required, the amount of such Gross-Up Payment and the assumptions to be utilized in arriving at such determination, shall be made by Deloitte & Touche LLP (the “Accounting Firm”). The Accounting Firm shall provide detailed supporting calculations both to the Corporation and the Executive within 15 business days of the receipt of notice from the Executive that there has been a Payment or such earlier time as is requested by the Corporation. All fees and expenses of the Accounting Firm shall be borne solely by the Corporation. Any Gross-Up Payment, as determined pursuant to this Section 13, shall be paid by the Corporation to the Executive within 5 days of the receipt of the Accounting Firm’s determination. Any determination by the Accounting Firm shall be binding upon the Corporation and the Executive in the absence of manifest error. As a result of the uncertainty in the application of Section 4999 of the Code at the time of the initial determination by the Accounting Firm hereunder, it is possible that Gross-Up Payments that will not have been made by the Corporation should have been made (the “Underpayment”), consistent with the calculations required to be made hereunder. In the event the Corporation exhausts its remedies pursuant to Section 13(c) and the Executive

thereafter is required to make a payment of any Excise Tax, the Accounting Firm shall determine the amount of the Underpayment that has occurred and any such Underpayment shall be promptly paid by the Corporation to or for the benefit of the Executive.

(c) The Executive shall notify the Corporation in writing of any claim by the Internal Revenue Service that, if successful, would require the payment by the Corporation of the Gross-Up Payment. Such notification shall be given as soon as practicable, but no later than 10 business days after the Executive is informed in writing of such claim. The Executive shall apprise the Corporation of the nature of such claim and the date on which such claim is requested to be paid. The Executive shall not pay such claim prior to the expiration of the 30-day period following the date on which the Executive gives such notice to the Corporation (or such shorter period ending on the date that any payment of taxes with respect to such claim is due). If the Corporation notifies the Executive in writing prior to the expiration of such period that the Corporation desires to contest such claim, the Executive shall:

(1) give the Corporation any information reasonably requested by the Corporation relating to such claim,

(2) take such action in connection with contesting such claim as the Corporation shall reasonably request in writing from time to time, including, without limitation, accepting legal representation with respect to such claim by an attorney reasonably selected by the Corporation,

(3) cooperate with the Corporation in good faith in order effectively to contest such claim, and

(4) permit the Corporation to participate in any proceedings relating to such claim;

provided, however, that the Corporation shall bear and pay directly all costs and expenses (including additional interest and penalties) incurred in connection with such contest, and shall indemnify and hold the Executive harmless, on an after-tax basis, for any Excise Tax or income tax (including interest and penalties) imposed as a result of such representation and payment of costs and expenses. Without limitation on the foregoing provisions of this Section 13(c), the Corporation shall control all proceedings taken in connection with such contest, and, at its sole discretion, may pursue or forgo any and all administrative appeals, proceedings, hearings and conferences with the applicable taxing authority in respect of such claim and may, at its sole discretion, either pay the tax claimed to the appropriate taxing authority on behalf of the Executive and direct the Executive to sue for a refund or contest the claim in any permissible manner, and the Executive agrees to prosecute such contest to a determination before any administrative tribunal, in a court of initial jurisdiction and in one or more appellate courts, as the Corporation shall determine; provided, however, that, if the Corporation pays such claim and directs the Executive to sue for a refund, the Corporation shall indemnify and hold the Executive harmless, on an after-tax basis, from any Excise Tax or income tax

(including interest or penalties) imposed with respect to such payment or with respect to any imputed income in connection with such payment; and provided, further, that any extension of the statute of limitations relating to payment of taxes for the taxable year of the Executive with respect to which such contested amount is claimed to be due is limited solely to such contested amount. Furthermore, the Corporation’s control of the contest shall be limited to issues with respect to which the Gross-Up Payment would be payable hereunder, and the Executive shall be entitled to settle or contest, as the case may be, any other issue raised by the Internal Revenue Service or any other taxing authority.

(d) If, after the receipt by the Executive of a Gross-Up Payment or payment by the Corporation of an amount on the Executive’s behalf pursuant to Section 13(c), the Executive becomes entitled to receive any refund with respect to the Excise Tax to which such Gross-Up Payment relates or with respect to such claim, the Executive shall (subject to the Corporation’s complying with the requirements of Section 13(c), if applicable) promptly pay to the Corporation the amount of such refund (together with any interest paid or credited thereon after taxes applicable thereto). If, after payment by the Corporation of an amount on the Executive’s behalf pursuant to Section 13(c), a determination is made that the Executive shall not be entitled to any refund with respect to such claim and the Corporation does not notify the Executive in writing of its intent to contest such denial of refund prior to the expiration of 30 days after such determination, then the amount of such payment shall offset, to the extent thereof, the amount of Gross-Up Payment required to be paid.

(e) Notwithstanding any other provision of this Section 13, the Corporation may, in its sole discretion, withhold and pay over to the Internal Revenue Service or any other applicable taxing authority, for the benefit of the Executive, all or any portion of any Gross-Up Payment, and the Executive hereby consents to such withholding.

(f) Definitions. The following terms shall have the following meanings for purposes of this Section 13.

(i) “Excise Tax” shall mean the excise tax imposed by Section 4999 of the Code, together with any interest or penalties imposed with respect to such excise tax.

(ii) A “Payment” shall mean any payment or distribution in the nature of compensation (within the meaning of Section 280G(b)(2) of the Code) to or for the benefit of the Executive, whether paid or payable pursuant to this Agreement or otherwise.”

3. Except as explicitly set forth herein, the Agreement will remain in full force and effect.

IN WITNESS WHEREOF, the Executive and the Corporation have caused this Amendment to the Agreement to be executed as of the date first specified above.