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                                                                     EXHIBIT 4.6

                             PETROLSOFT CORPORATION
                             1998 STOCK OPTION PLAN


1.   PURPOSE. This Stock Option Plan (the "Plan") is intended to serve as an
     incentive to, and to encourage stock ownership by, certain eligible
     participants rendering services to PetrolSoft Corporation, a California
     corporation (the "Corporation"), and certain affiliates as set forth below,
     so that they may acquire or increase their proprietary interest in the
     Corporation.

2.   ADMINISTRATION.

     2.1  COMMITTEE. The Plan shall be administered by the Board of Directors of
          the Corporation (the "Board of Directors") or a committee of three or
          more members appointed by the Board of Directors (the "Committee").
          The Committee shall select one of its members as Chairman and shall
          appoint a Secretary, who need not be a member of the Committee. The
          Committee shall hold meetings at such times and places as it may
          determine and minutes of such meetings shall be recorded. Acts by a
          majority of the Committee in a meeting at which a quorum is present
          and acts approved in writing by a majority of the members of the
          Committee shall be valid acts of the Committee. No member of the
          Committee shall vote on any matter concerning his or her own
          participation in the Plan.

     2.2  TERM. If the Board of Directors selects a Committee, the members of
          the Committee shall serve on the Committee for the period of time
          determined by the Board of Directors and shall be subject to removal
          by the Board of Directors at any time. The Board of Directors may
          terminate the function of the Committee at any time and resume all
          powers and authority previously delegated to the Committee.

     2.3  AUTHORITY. The Committee shall have sole discretion and authority to
          grant options under the Plan to eligible participants rendering
          services to the Corporation or any "parent" or "subsidiary" of the
          Corporation ("Parent or Subsidiary"), as defined in Section 424 of the
          Internal Revenue Code of 1986, as amended (the "Code"), at such times,
          under such terms and in such amounts as it may decide. For purposes of
          this Plan and any Stock Option Agreement (as defined below), the term
          "Corporation" shall include any Parent or Subsidiary, if applicable.
          Subject to the express provisions of the Plan, the Committee shall
          have complete authority to interpret the Plan, to prescribe, amend and
          rescind the rules and regulations relating to the Plan, to determine
          the details and provisions of any Stock Option Agreement, to
          accelerate any options granted under the Plan and to make all other
          determinations necessary or advisable for the administration of the
          Plan.

     2.4  TYPE OF OPTION. The Committee shall have full authority and discretion
          to determine, and shall specify, whether the eligible individual will
          be granted options intended to qualify as incentive options under
          Section 422 of the Code ("Incentive Options") or options which are not
          intended to qualify under Section 422 of the Code ("Non-Qualified
          Options"); provided, however, that Incentive Options shall only be
          granted to employees of the Corporation, or a Parent or Subsidiary
          thereof, and shall be subject to the special limitations set forth
          herein attributable to Incentive Options.

     2.5  INTERPRETATION. The interpretation and construction by the Committee
          of any provisions of the Plan or of any option granted under the Plan
          shall be final and binding on all parties having an interest in this
          Plan or any option granted hereunder. No member of the Committee shall
          be liable for any action or determination made in good faith with
          respect to the Plan or any option granted under the Plan.

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3.   ELIGIBILITY.

     3.1  GENERAL. All directors, officers, employees of and certain persons
          rendering services to the Corporation, or any Parent or Subsidiary,
          relative to the Corporation's, or any Parent's or Subsidiaries',
          management, operation or development shall be eligible to receive
          options under the Plan. The selection of recipients of options shall
          be within the sole and absolute discretion of the Committee. No person
          shall be granted an option under this Plan unless such person has
          executed the grant representation letter set forth on Exhibit "A," as
          such Exhibit may be amended by the Committee from time to time and no
          person shall be granted an Incentive Option under this Plan unless
          such person is an employee of the Corporation, or a Parent or
          Subsidiary, on the date of grant.

     3.2  SHAREHOLDERS AGREEMENT; S CORPORATION STATUS. No optionee shall be
          entitled to receive any common stock of the Corporation upon the
          exercise of an option granted under this Plan unless such optionee has
          first executed the Shareholders Agreement, attached hereto as Exhibit
          "B," as such Exhibit may be amended from time to time by the Company
          and the signatories thereto. Notwithstanding anything herein to the
          contrary, no optionee shall be entitled to receive any common stock of
          the Corporation upon the exercise of a option granted under this Plan
          if it would in any way disqualify the Corporation as an "S"
          Corporation, including (but not by way of limitation) issuance of
          shares of common stock by the Company to more than seventy-five (75)
          persons.

     3.3  TERMINATION OF ELIGIBILITY. If an optionee ceases to be employed by
          the Corporation, or its Parent or Subsidiary, is no longer an officer
          or member of the Board of Directors of the Corporation or no longer
          performs services for the Corporation, or its Parent or Subsidiary for
          any reason (other than for "cause," as hereinafter defined, or such
          optionee's death), any option granted hereunder to such optionee shall
          expire three months after the occurrence giving rise to such
          termination of eligibility (or 1 year in the event an optionee is
          "disabled," as defined in Section 22(e)(3) of the Code) or upon the
          date it expires by its terms, whichever is earlier. Any option that
          has not vested in the optionee as of the date of such termination
          shall immediately expire and shall be null and void. The Committee
          shall, in its sole and absolute discretion, decide whether an
          authorized leave of absence or absence for military or governmental
          service, or absence for any other reason, shall constitute termination
          of eligibility for purposes of this Section.

          3.3.1   If an optionee ceases to be employed by the Corporation, or
                  its Parent or Subsidiary, is no longer an officer or member
                  of the Board of Directors of the Corporation, or no longer
                  performs services for the Corporation, or its Parent or
                  Subsidiary and such termination is as a result of "cause,"
                  as hereinafter defined, then all options granted hereunder
                  to such optionee shall expire on the date of the occurrence
                  giving rise to such termination of eligibility or upon the
                  date it expires by its terms, whichever is earlier, and such
                  optionee shall have no rights with respect to any
                  unexercised options. For purposes of this Plan, "cause"
                  shall mean an optionee's personal dishonesty, misconduct,
                  breach of fiduciary duty, incompetence, intentional failure
                  to perform stated obligations, willful violation of any law,
                  rule, regulation or final cease and desist order, or any
                  material breach of any provision of this Plan, any Stock
                  Option Agreement or any employment agreement.

     3.4  DEATH OF OPTIONEE AND TRANSFER OF OPTION. In the event an optionee
          shall die, an option may be exercised (subject to the condition that
          no option shall be exercisable after its expiration and only to the
          extent that the optionee's right to exercise such option had accrued
          at the time of the optionee's death) at any time within six months
          after the optionee's death by the executors or administrators of the
          optionee or by any person or persons who shall have acquired the
          option directly from the optionee by bequest or inheritance. Any
          option that has not vested in the optionee as of the date of death or
          termination of employment, whichever is earlier, shall immediately
          expire and shall be null and void. No option shall be transferable by
          the optionee other than by will or the laws of intestate succession.


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     3.5  LIMITATION ON OPTIONS. No person shall be granted any Incentive Option
          to the extent that the aggregate fair market value of the Stock (as
          defined below) to which such options are exercisable for the first
          time by the optionee during any calendar year (under all plans of the
          Corporation as determined under Section 422(d) of the Code) exceeds
          $100,000.

4.   IDENTIFICATION OF STOCK. The Stock, as defined herein, subject to the
     options shall be shares of the Corporation's authorized but unissued or
     acquired or reacquired common stock (the "Stock"). The aggregate number of
     shares subject to outstanding options shall not exceed 600,000 shares of
     Stock (subject to adjustment as provided in Section 6). If any option
     granted hereunder shall expire or terminate for any reason without having
     been exercised in full, the unpurchased shares subject thereto shall again
     be available for purposes of this Plan.

5.   TERMS AND CONDITIONS OF OPTIONS. Any option granted pursuant to the Plan
     shall be evidenced by an agreement ("Stock Option Agreement") in such form
     as the Committee shall from time to time determine, which agreement shall
     comply with and be subject to the following terms and conditions:

     5.1  NUMBER OF SHARES. Each option shall state the number of shares of
          Stock to which it pertains.

     5.2  OPTION EXERCISE PRICE. Each option shall state the option exercise
          price, which shall be determined by the Committee; provided, however,
          that (i) the exercise price of any Incentive Option shall not be less
          than the fair market value of the Stock, as determined by the
          Committee, on the date of grant of such option, (ii) the exercise
          price of any Incentive Option granted to an employee who owns more
          than 10% of the total combined voting power of all classes of the
          Corporation's stock, as determined for purposes of Section 422 of the
          Code, shall not be less than 110% of the fair market value of the
          Stock, as determined by the Committee, on the date of grant of such
          option, and (iii) the exercise price of any Non-Qualified Option shall
          not be less than 90% of the fair market value of the Stock, as
          determined by the Committee, on the date of grant of such option.

     5.3  TERM OF OPTION. The term of an option granted hereunder shall be
          determined by the Committee at the time of grant, but shall not exceed
          ten years from the date of the grant. The term of any Incentive Option
          granted to an employee who owns more than 10% of the total combined
          voting power of all classes of the Corporation's stock as determined
          for purposes of Section 422 of the Code, shall in no event exceed five
          years from the date of grant. All options shall be subject to early
          termination as set forth in this Plan. In no event shall any option be
          exercisable after the expiration of its term.

     5.4  METHOD OF EXERCISE. An option shall be exercised by written notice to
          the Corporation by the optionee (or successor in the event of death)
          and execution by the optionee of an exercise representation letter in
          the form set forth on Exhibit "C," as such Exhibit may be amended by
          the Committee from time to time. Such written notice shall state the
          number of shares with respect to which the option is being exercised
          and designate a time, during normal business hours of the Corporation,
          for the delivery thereof ("Exercise Date"), which time shall be at
          least 30 days after the giving of such notice unless an earlier date
          shall have been mutually agreed upon. At the time specified in the
          written notice, the Corporation shall deliver to the optionee at the
          principal office of the Corporation, or such other appropriate place
          as may be determined by the Committee, a certificate or certificates
          for such shares. Notwithstanding the foregoing, the Corporation may
          postpone delivery of any certificate or certificates after notice of
          exercise for such reasonable period as may be required to comply with
          any applicable listing requirements of any securities exchange. In the
          event an option shall be exercisable by any person other than the
          optionee, the required notice under this Section shall be accompanied
          by appropriate proof of the right of such person to exercise the
          option.

     5.5  MEDIUM AND TIME OF PAYMENT. The option exercise price shall be payable
          in full on or before the option Exercise Date in cash or certified
          bank or cashier's check.

     5.6  FAIR MARKET VALUE.  The fair market value of a share of Stock on any
          relevant date shall be determined in accordance with the following
          provisions:

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          5.6.1   If the Stock is at the time neither listed nor admitted to
                  trading on any stock exchange nor traded in the
                  over-the-counter market, then the fair market value shall be
                  determined by the Committee after taking into account such
                  factors as the Committee shall deem appropriate.

          5.6.2   If the Stock is not at the time listed or admitted to trading
                  on any stock exchange but is traded in the over-the-counter
                  market, the fair market value shall be the mean between the
                  highest bid and lowest asked prices (or, if such information
                  is available, the closing selling price) of one share of
                  Stock on the date in question in the over-the-counter
                  market, as such prices are reported by the National
                  Association of Securities Dealers through its NASDAQ system
                  or any successor system. If there are no reported bid and
                  asked prices (or closing selling price) for the Stock on the
                  date in question, then the mean between the highest bid
                  price and lowest asked price (or the closing selling price)
                  on the last preceding date for which such quotations exist
                  shall be determinative of fair market value.

          5.6.3   If the Stock is at the time listed or admitted to trading on
                  any stock exchange, then the fair market value shall be the
                  closing selling price of one share of Stock on the date in
                  question on the stock exchange determined by the Committee
                  to be the primary market for the Stock, as such price is
                  officially quoted in the composite tape of transactions on
                  such exchange. If there is no reported sale of Stock on such
                  exchange on the date in question, then the fair market value
                  shall be the closing selling price on the exchange on the
                  last preceding date for which such quotation exists.

     5.7  RIGHTS AS A SHAREHOLDER. An optionee or successor shall have no rights
          as a shareholder with respect to any Stock underlying any option until
          the date of the issuance to such optionee of a certificate for such
          Stock. No adjustment shall be made for dividends (ordinary or
          extraordinary, whether in cash, securities or other property) or
          distributions or other rights for which the record date is prior to
          the date such Stock certificate is issued, except as provided in
          Section 6.

     5.8  MODIFICATION, EXTENSION AND RENEWAL OF OPTIONS. Subject to the terms
          and conditions of the Plan, the Committee may modify, extend or renew
          outstanding options granted under the Plan, or accept the surrender of
          outstanding options (to the extent not exercised) and authorize the
          granting of new options in substitution therefor.

     5.9  OTHER PROVISIONS. The Stock Option Agreements shall contain such other
          provisions, including without limitation, restrictions or conditions
          upon the exercise of options, as the Committee shall deem advisable.

6.   ADJUSTMENTS UPON CHANGES IN CAPITALIZATION.

     6.1  SUBDIVISION OR CONSOLIDATION. Subject to any required action by
          shareholders of the Corporation, the number of shares of Stock covered
          by each outstanding option, and the exercise price thereof, shall be
          proportionately adjusted for any increase or decrease in the number of
          issued shares of Stock of the Corporation resulting from a subdivision
          or consolidation of shares or the payment of a stock dividend (but
          only on the Stock) or any other increase or decrease in the number of
          such shares effected without receipt of consideration by the
          Corporation. Any fraction of a share subject to option that would
          otherwise result from an adjustment pursuant to this Section shall be
          rounded downward to the next full number of shares without other
          compensation or consideration to the holder of such option.

     6.2  CAPITAL TRANSACTIONS. Upon a sale or exchange of all or substantially
          all of the assets of the Corporation, a merger or consolidation in
          which the Corporation is not the surviving corporation, a merger,
          reorganization or consolidation in which the Corporation is the
          surviving corporation and shareholders of the Corporation exchange
          their stock for securities or property, a liquidation of the
          Corporation or similar transaction ("Capital Transaction"), this Plan
          and each option issued under this Plan, whether vested or unvested,
          shall terminate, unless such options are assumed by a successor
          corporation in a merger or consolidation, 15 days prior to such
          Capital Transaction; provided, however, that unless the outstanding
          options are assumed by a successor corporation in a merger or
          consolidation, subject to terms approved by the Committee or the
          options are repurchased pursuant to Section 8, all optionees will have
          the right, until 15 days prior to such Capital Transaction, to
          exercise all vested options. The Corporation shall, subject to

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          any nondisclosure provisions, attempt to provide optionees at least 15
          days notice of the option termination date. The Committee may (but
          shall not be obligated to) (i) accelerate the vesting of any option
          (provided, however, the Committee may not accelerate such vesting if
          acceleration would cause the Capital Transaction to not qualify to be
          recorded as a pooling of interests for accounting purposes), or (ii)
          apply the foregoing provisions, including but not limited to
          termination of this Plan and any options granted pursuant to the Plan,
          in the event there is a sale of 50% or more of the stock of the
          Corporation in any two-year period or a transaction similar to a
          Capital Transaction.

     6.3  ADJUSTMENTS. To the extent that the foregoing adjustments relate to
          stock or securities of the Corporation, such adjustments shall be made
          by the Committee, whose determination in that respect shall be final,
          binding and conclusive.

     6.4  ABILITY TO ADJUST. The grant of an option pursuant to the Plan shall
          not affect in any way the right or power of the Corporation to make
          adjustments, reclassifications, reorganizations or changes of its
          capital or business structure or to merge, consolidate, dissolve,
          liquidate, sell or transfer all or any part of its business or assets.

     6.5  NOTICE OF ADJUSTMENT. Whenever the Corporation shall take any action
          resulting in any adjustment provided for in this Section, the
          Corporation shall forthwith deliver notice of such action to each
          optionee, which notice shall set forth the number of shares subject to
          the option and the exercise price thereof resulting from such
          adjustment.

     6.6  LIMITATION ON ADJUSTMENTS.  Any adjustment, assumption or substitution
          of an Incentive Option shall comply with Section 425 of the Code, if
          applicable.

7.   NONASSIGNABILITY. Options granted under this Plan may not be sold, pledged,
     assigned or transferred in any manner other than by will or by the laws of
     intestate succession, and may be exercised during the lifetime of an
     optionee only by such optionee. Any transfer by the optionee of any option
     granted under this Plan in violation of this Section shall void such option
     and any Stock Option Agreement entered into by the optionee and the
     Corporation regarding such transferred option shall be void and have no
     further force or effect. No option shall be pledged or hypothecated in any
     way, nor shall any option be subject to execution, attachment or similar
     process.

8.   REPURCHASE OPTION.

     8.1  The Corporation shall have the right to purchase all Stock held by an
          optionee or any unexercised option held by an optionee which has been
          obtained pursuant to the Plan, together with any rights, securities or
          additional stock that has been received pursuant to a stock dividend,
          stock split, reorganization or other similar transaction that has been
          received as a result of an employee option or Stock acquired pursuant
          thereto in the event (i) an optionee terminates his or her services
          with the Corporation, or any Parent or Subsidiary thereof, or (ii) the
          Corporation so elects, in the event of a Capital Transaction. The
          price paid for any unexercised option or Stock shall be in cash at the
          fair market value of such option or Stock as determined herein. The
          fair market value assigned to any option shall be the fair market
          value of the Stock as to which it is exercisable reduced by the
          exercise price. The parties shall first negotiate in good faith to
          reach an agreement as to the value of the option or Stock. Absent an
          agreement within 30 days, the parties shall select one appraiser to
          determine the value of the Stock. In the event the parties cannot
          agree as to an appraiser, then each party shall appoint one appraiser
          and the two appraisers shall jointly determine a third appraiser. In
          the event the two appraisers cannot determine a third appraiser, such
          third appraiser shall be appointed by a Judge of the Superior Court of
          the County of San Diego, California. Such appraisers shall make their
          determination of the fair market value of the Stock, and the average
          of the two appraisers whose valuations are closest to each other shall
          control. Any appraiser selected by any party shall be an appraiser
          experienced in the area of valuing similar stock. The Corporation and
          the optionee, or successor, shall each pay for one-half of the cost of
          any such appraisal. If the Corporation desires to purchase the Stock
          or options held by an employee as set forth in this Section, then the
          Corporation shall provide written notice to such optionee at such
          optionee's last known address within 90 days after the termination of
          such optionee's employment, or at least 30 days prior to a Capital
          Transaction.

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     8.2  The Committee may assign the Corporation's repurchase option under
          this Section to any person selected by the Committee including one or
          more of the shareholders of the Corporation.

          8.2.1  The repurchase option set forth in this Section shall terminate
                 upon the consummation of an underwritten public offering of the
                 Corporation's Stock registered under the Securities Act of
                 1933, as amended (the "Act").

9.   RIGHT OF FIRST REFUSAL.

     9.1  Stock issued pursuant to this Plan together with any rights,
          securities or additional stock that have been received pursuant to a
          stock dividend, stock split, reorganization or other transaction that
          has been received as a result of an employee option or stock acquired
          pursuant thereto shall be subject to a right of first refusal by the
          Corporation in the event the holder of such shares proposes to sell,
          pledge or otherwise transfer said shares or any interest in said
          shares to any person or entity. Any holder of shares of Stock (or
          other securities) acquired under the Plan desiring to transfer such
          Stock (or other securities) or any interest therein shall give written
          notice to the Corporation describing the proposed transfer, including
          the price of shares proposed to be transferred, the proposed transfer
          price and terms, and the name and address of the proposed transferee.
          Unless otherwise agreed by the Corporation and the holder of such
          shares, repurchases by the Corporation under this Section shall be at
          the lesser of (i) the proposed price and terms specified in the notice
          to the Corporation; or (ii) the fair market value of the Stock as
          determined in Section 8.1. The Corporation's rights under this Section
          shall be freely assignable.

     9.2  If the Corporation fails to exercise its right of first refusal within
          30 days (as such period may be extended to determine the fair market
          value of the Stock pursuant to the terms of Section 8.1) from the date
          upon which the Corporation received the shareholder's written notice,
          the shareholder may, within the next 90 days, conclude a transfer of
          the exact number of shares covered by said notice on terms not more
          favorable to the transferee than those described in the notice. Any
          subsequent proposed transfer by such transferee shall again be subject
          to the Corporation's right of first refusal. If the Corporation
          exercises its right of first refusal, the shareholder shall endorse
          and deliver to the Corporation the stock certificates representing the
          shares being repurchased, and the Corporation shall promptly pay the
          shareholder the total repurchase price as set forth in the terms of
          the agreement. The holders of shares being repurchased pursuant to
          this Section shall cease to have any rights with respect to such
          shares immediately upon repurchase.

     9.3  No written notice of a proposed transfer shall be required under this
          Section and no right of first refusal shall exist with respect to
          transfers by will or the laws of intestate succession.

     9.4  The right of first refusal set forth in this Section shall terminate
          upon the consummation of an underwritten public offering of the
          Corporation's Stock registered under the Securities Act of 1933, as
          amended (the "Act").

     9.5  Any attempted transfer of any Stock or securities subject to this
          right of first refusal which is not made in compliance with this
          Section shall be null and void.

     9.6  The Committee may assign the Corporation's repurchase option under
          this Section to any person selected by the Committee including one or
          more or the shareholders of the Corporation.

10.  NO RIGHT OF EMPLOYMENT. Neither the grant nor exercise of any option nor
     anything in this Plan shall impose upon the Corporation or any other
     corporation any obligation to employ or continue to employ any optionee.
     The right of the Corporation and any other corporation to terminate any
     employee shall not be diminished or affected because an option has been
     granted to such employee.

11.  TERM OF PLAN. This Plan is effective on the date the Plan is adopted by the
     Board of Directors and options may be granted pursuant to the Plan from
     time to time within a period of ten (10) years from such date, or the date
     of any required shareholder approval required under the Plan, if earlier.
     Termination of the Plan shall not affect any option theretofore granted.

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12.  AMENDMENT OF THE PLAN. The Board of Directors of the Corporation may,
     subject to any required shareholder approval, suspend, discontinue or
     terminate the Plan, or revise or amend it in any respect whatsoever with
     respect to any shares of Stock at that time not subject to options.

13.  APPLICATION OF FUNDS. The proceeds received by the Corporation from the
     sale of Stock pursuant to options may be used for general corporate
     purposes.

14.  RESERVATION OF SHARES. The Corporation, during the term of this Plan,
     shall at all times reserve and keep available such number of shares of
     Stock as shall be sufficient to satisfy the requirements of the Plan.

15.  NO OBLIGATION TO EXERCISE OPTION. The granting of an option shall not
     impose any obligation upon the optionee to exercise such option.

16.  APPROVAL OF BOARD OF DIRECTORS AND SHAREHOLDERS. The Plan shall not take
     effect until approved by the Board of Directors of the Corporation. This
     Plan shall be approved by a vote of the shareholders within 12 months from
     the date of approval by the Board of Directors. In the event such
     shareholder vote is not obtained, all options granted hereunder, whether
     vested or unvested, shall be null and void.

17.  WITHHOLDING TAXES. Notwithstanding anything else to the contrary in this
     Plan or any Stock Option Agreement, the exercise of any option shall be
     conditioned upon payment by such optionee in cash, or other provisions
     satisfactory to the Committee, of all local, state, federal or other
     withholding taxes applicable, in the Committee's judgment, to the exercise
     or to later disposition of shares acquired upon exercise of an option
     (including any repurchase of an option or the Stock).

18.  PARACHUTE PAYMENTS. Any outstanding option under the Plan may not be
     accelerated to the extent any such acceleration of such option would, when
     added to the present value of other payments in the nature of compensation
     which becomes due and payable to the optionee would result in the payment
     to such optionee of an excess parachute payment under Section 280G of the
     Code. The existence of any such excess parachute payment shall be
     determined in the sole and absolute discretion of the Committee.

19.  SECURITIES LAWS COMPLIANCE. Notwithstanding anything contained herein, the
     Corporation shall not be obligated to grant any option under this Plan or
     to sell, issue or effect any transfer of any Stock unless such grant, sale,
     issuance or transfer is at such time effectively (i) registered or exempt
     from registration under the Act and (ii) qualified or exempt from
     qualification under the California Corporate Securities Law of 1968 and any
     other applicable state securities laws. As a condition to exercise of any
     option, each optionee shall make such representations as may be deemed
     appropriate by counsel to the Corporation for the Corporation to use any
     available exemption from registration under the Act or any applicable state
     securities law.

20.  RESTRICTIVE LEGENDS.  The certificates representing the Stock issued upon
     exercise of options granted pursuant to this Plan will bear the following
     legends giving notice of restrictions on transfer under the Act and this
     Plan, as follows:

     20.1 THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE BEEN ISSUED OR
          TRANSFERRED IN A TRANSACTION WHICH WAS NOT REGISTERED UNDER THE
          SECURITIES ACT OF 1933, AS AMENDED, IN RELIANCE UPON AN EXEMPTION
          AFFORDED BY SUCH ACT. NO SALE OR TRANSFER OF THESE SHARES SHALL BE
          MADE, NO ATTEMPTED SALE OR TRANSFER SHALL BE VALID, AND THE ISSUER
          SHALL NOT BE REQUIRED TO GIVE ANY EFFECT TO ANY SUCH TRANSACTION
          UNLESS (A) SUCH TRANSACTION SHALL HAVE BEEN DULY REGISTERED UNDER THE
          ACT OR (B) THE ISSUER SHALL HAVE FIRST RECEIVED AN OPINION OF COUNSEL
          SATISFACTORY TO IT THAT SUCH REGISTRATION IS NOT REQUIRED.

     20.2 THE SALE, TRANSFER, HYPOTHECATION, OR ENCUMBRANCE OF THE SHARES
          REPRESENTED BY THIS CERTIFICATE IS RESTRICTED BY THE PROVISIONS OF A
          STOCK

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          OPTION AGREEMENT DATED DECEMBER __, 1998 AND A STOCK OPTION PLAN DATED
          DECEMBER __, 1998, A COPY OF WHICH MAY BE INSPECTED AT THE
          CORPORATION'S PRINCIPAL OFFICE.

          Any other legends required by applicable state securities laws as
          determined by the Committee.

7.   NOTICES. Any notice to be given under the terms of the Plan shall be
     addressed to the Corporation in care of its Secretary at its principal
     office, and any notice to be given to an optionee shall be addressed to
     such optionee at the address maintained by the Corporation for such person
     or at such other address as the optionee may specify in writing to the
     Corporation.

     As adopted by the Board of Directors as of December __, 1998.


                                     PETROLSOFT CORPORATION, a California
                                     corporation


                                      By:
                                         --------------------------------------
                                         David J. Gamboa, President


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