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                                                                   EXHIBIT 10.13

                        Revised Stock Option Agreement

                           Onyx Software Corporation

I.   OPTION GRANT.  ONYX SOFTWARE CORPORATION, a Washington corporation (the
     "Company") hereby grants a nonqualified stock option to purchase a total of
     500,000 shares of Common Stock of the Company (the "Option"), par value
     $0.01 per share, (the "Common Stock") as of April 18, 2001 (the "Grant
     Date") to BRIAN HENRY (the "Optionee"), pursuant to and subject in all
     respects to the terms and provisions of the Company's 1998 Stock Incentive
     Compensation Plan (the "1998 Plan"), as modified by this Revised Stock
     Option Agreement. This Option shall be governed by, and construed in
     accordance with, the laws of the state of Washington without regard for
     principles of conflict of laws. This Revised Stock Option Agreement
     supersedes the original Stock Option Agreement granted to Optionee by the
     Company's board of directors on March 16, 2001.

II.  VESTING SCHEDULE.  The Vesting Initiation Date shall be April 4, 2001. This
     Option shall vest and become exercisable as to 25% of the total number of
     shares of Common Stock covered by this Option on the one year anniversary
     of the Vesting Initiation Date and an additional 2.0833% of the shares
     covered by the Option shall vest each month thereafter, with the result
     that the Option shall be fully vested and exercisable four years after the
     Vesting Initiation Date. Notwithstanding the foregoing, if Optionee's
     employment with the Company terminates in a Qualifying Termination (as
     defined in the Employment Agreement by and between the Company and Optionee
     entered into as of the 14th day of March, 2001 (the "Employment
     Agreement")), this Option shall, immediately upon such Qualifying
     Termination, become fully vested and become exercisable pursuant to the
     terms of Subsection 12(d) of the Employment Agreement.

III.  PRICE.  The Option exercise price per share (the "Exercise Price") as
      determined by the Board of Directors (the "Board") of the Company is
      $3.03. The Exercise Price shall be paid by delivery of cash or, subject to
      the discretion of the Board, by delivery of an approved equivalent to
      cash.

IV.  PURCHASE FOR INVESTMENT.  This Option may not be exercised if the issuance
     of shares of Common Stock pursuant to an exercise would constitute a
     violation of any applicable federal or state securities or other law or
     valid regulation. Any other provision of this Option notwithstanding, the
     obligation of the Company to issue shares pursuant to an exercise of the
     Option shall be subject to all applicable laws, rules and regulations and
     such approval by any regulatory body as may be required. The Company
     reserves the right to restrict, in whole or in part, the delivery of shares
     prior to the satisfaction of all legal requirements relating to the
     issuance of such shares, to their registration, qualification or listing or
     to an exemption from registration, qualification or listing.

V.  NON-ASSIGNABILITY.  The Option may not be transferred or hypothecated in any
    manner and shall only be exercisable by the Optionee or his legal
    representative. The terms of this Option shall be binding upon the
    executors, administrators, heirs, successors, and assigns of the Optionee.
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VI.  EXERCISE.

     A.   This Option shall be exercisable, to the extent of the number of
          shares purchasable by Optionee at the date of termination, only (a)
          within one year after such termination if the Optionee's termination
          is coincident with the Optionee's death or Disability (as defined in
          the Employment Agreement) or (b) within ninety days after the date
          that Optionee ceases to be an employee, director, officer, consultant,
          agent, advisor or independent contractor of the Company or a
          subsidiary if termination of the Optionee's employment or services is
          for any reason other than death, Disability, or a Qualifying
          Termination, but in no event later than the remaining Term of the
          Option or (c) within one hundred twenty (120) days after the date that
          Optionee ceases to be an employee, director, officer, consultant,
          agent, advisor or independent contractor of the Company or a
          subsidiary if termination of the Optionee's employment or services
          results from a Qualifying Termination, but in no event later than the
          remaining Term of the Option. Notwithstanding the foregoing provisions
          of Subsection V.I.A.(c) above, in the event that such options are not
          exercisable within any portion of such 120 day period, by reason of
          applicable securities laws, the rules of any stock exchange on which
          the shares are listed, any agreement with an underwriter, or any
          agreement with or policy of the Company, the 120-day period shall be
          correspondingly extended, provided that in no event shall extension
          continue later than the remaining Term of the Option. Any portion of
          this Option exercisable at the time of the Optionee's death may be
          exercised, to the extent of the number of shares purchasable by the
          Optionee at the date of the Optionee's death, by the personal
          representative of the Optionee's estate or the person(s) to whom the
          Optionee's rights under the Option have passed by will or the
          applicable laws of descent and distribution, at any time or from time
          to time within one year after the date of death, but in no event later
          than the remaining Term of the Option.

     B.   This Option may not be exercised more than ten (10) years from the
          date hereof (the "Term"), and may be exercised during the Term only in
          accordance with the terms and provisions set forth herein.

     C.   In the event that Optionee's employment terminates in a Qualifying
          Termination within two years of a Corporate Transaction (as defined
          below) involving the Company, this Option shall immediately accelerate
          so as to become fully vested and exercisable. A "Corporate
          Transaction" means any of the following events: (a) consummation of
          any merger or consolidation of the Company in which the Company is not
          the continuing or surviving corporation, or pursuant to which shares
          of the Common Stock are converted into cash, securities or other
          property, if following such merger or consolidation the holders of the
          Company's outstanding voting securities immediately prior to such
          merger or consolidation own less than a majority of the outstanding
          voting securities of the surviving corporation; (b) consummation of
          any sale, lease, exchange or other transfer in one transaction or a
          series of related transactions of all or substantially all of the
          Company's assets other than a transfer of the Company's assets to a
          majority-owned subsidiary corporation of the Company; or (c) approval
          by the holders of

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          the Common Stock of any plan or proposal for the liquidation or
          dissolution of the Company. Ownership of voting securities shall take
          into account and shall include ownership as determined by applying
          Rule 13d-3(d)(1)(i) (as in effect on the date hereof) under the
          Securities and Exchange Act of 1934, as amended. The accelerated
          vesting of the Option pursuant to this Section VI(C) or pursuant to
          the Employment Agreement shall not be adversely altered or rendered
          null and void, without Optionee's express written consent, even if
          such accelerated vesting would preclude a Corporate Transaction or
          other transaction involving the Company from qualifying for financial
          accounting treatment of such transaction as a pooling of interests
          under APB Opinion No. 16.

     D.   This Option may be exercised for all or part of the shares eligible
          for exercise by presenting a written notice (the "Notice") to the
          Company that this Option is exercised in strict accordance with the
          terms and provisions of this Option. The Company shall determine
          whether or not the Notice complies with the terms and provisions of
          this Option. Such Notice shall identify this Option, state the number
          of shares as to which the Option is exercised and be signed by the
          Optionee. Delivery of the cash or cash equivalent in payment for the
          shares to be purchased pursuant to the exercise of this Option shall
          accompany the Notice. The Letter of Investment, representations and
          such other documentation required by Section IV hereof shall also
          accompany the Notice. If the Optionee is deceased, the Notice shall be
          signed, and if the Optionee is Disabled, it may be signed, by the
          Optionee's legal representatives or beneficiaries, and in all
          instances shall be accompanied by evidence satisfactory to the Company
          and its transfer agent of the right of such person or persons to
          exercise this Option.

     E.   The Optionee shall make arrangements satisfactory to the Company for
          the satisfaction of any withholding tax obligations that arise in
          connection with his Option. The Company shall not be required to issue
          any shares of Common Stock until such obligations are satisfied.

VII.  MARKET STANDOFF.  In connection with any underwritten public offering by
      the Company of its equity securities pursuant to an effective registration
      statement filed under the Securities Act, Optionee shall not sell, make
      any short sale of, loan, hypothecate, pledge, grant any option for the
      purchase of, or otherwise dispose or transfer for value or otherwise agree
      to engage in any of the foregoing transactions with respect to, any shares
      issued pursuant to this Option without the prior written consent of the
      Company or its underwriters. Such limitations shall be in effect for such
      period of time as may be requested by the Company or such underwriters and
      agreed to by the Company's officers and directors with respect to their
      shares; provided, however, that in no event shall such period exceed 180
      days. Holders of shares issued pursuant to this Option shall be subject to
      the market standoff provisions of this paragraph only if the other
      officers and directors of the Company are also subject to similar
      arrangements. In the event of any stock split, stock dividend,
      recapitalization, combination of shares, exchange of shares or other
      change affecting the outstanding Common Stock effected as a class without
      the Company's receipt of consideration, then any new, substituted or
      additional securities distributed with respect to the purchased shares
      shall be immediately

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      subject to the provisions of this Section VII., to the same extent the
      purchased shares are at such time covered by such provisions. In order to
      enforce the limitations of this Section VII., the Company may impose stop-
      transfer instructions with respect to the purchased shares until the end
      of the applicable standoff period.

VIII.  EFFECT OF CHANGE IN COMMON STOCK SUBJECT TO OPTION.  If the outstanding
       shares of Common Stock shall at any time be changed or exchanged by
       declaration of a stock dividend, split-up, combination of shares, or
       recapitalization, the number and kind of shares subject to this Option,
       and the Exercise Price, shall be appropriately and equitably adjusted so
       as to maintain the proportionate number of shares subject to this Option
       and the Exercise Price in relation to the change in stock; provided,
       however, that no adjustment shall be made by reason of the distribution
       of subscription rights on outstanding stock.

IX.   AMENDMENT OR ALTERATION.  The Board may amend or alter this Option or the
      1998 Plan, except that no amendment or alteration shall be made which
      would impair the rights of the Optionee hereunder, without his consent,
      and, except further, this Option shall be subject to the requirement that,
      if, at any time the Board shall determine, in its discretion, that the
      listing, registration or qualification of the stock issuable or
      transferable upon exercise thereof upon any securities exchange or under
      any state or federal law or the consent or approval of any governmental
      regulatory body is necessary or desirable as a condition of, or in
      connection with, the granting of this Option or the issue, transfer, or
      purchase of shares hereunder, this Option may not be exercised in whole or
      in part unless such listing, registration, qualification, consent, or
      approval shall have been effected or obtained free of any conditions not
      acceptable to the Board.

X.   OPTION NOT A SERVICE CONTRACT.  This Option is not an employment contract
     and nothing in this Option shall be construed as giving Optionee any right
     to be retained in the employ of the Company or limit the Company's right to
     terminate the employment or services of Optionee.

XI.  NO RIGHTS AS A SHAREHOLDER.  The Optionee, or a transferee of the Optionee,
     shall have no rights as a shareholder with respect to any Common Stock
     covered by the Option until such person becomes entitled to receive such
     Common Stock by filing a Notice and paying the Exercise Price pursuant to
     the terms of this Option.

                                       ONYX SOFTWARE CORPORATION

                              By:          /s/ Brent Frei
                                 ----------------------------------------
                                         Chief Executive Officer

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If the following acknowledgment and acceptance is not executed within ten (10)
days of the effective date of this Option, it shall lapse and be treated for all
purposes as if it were never granted.

The Optionee agrees to be bound by all terms and conditions of the Option set
forth in this Revised Stock Option Agreement and in the 1998 Plan and
acknowledges and represents that he is familiar with and understands the terms
and provisions of this Option and the 1998 Plan.

Dated:   April 18, 2001


WITNESS:                                    OPTIONEE:
                                            /s/ Brian Henry
---------------------------------           ------------------------------------
                                            Brian Henry

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