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                                                                    EXHIBIT 10.1

                      OBJECTIVE SYSTEMS INTEGRATORS, INC.

                            1994 STOCK OPTION PLAN
                      (as amended through July 24, 1999)


1.   Purposes.  The purposes of this Stock Option Plan are to attract and retain
     --------
     the best available people for positions of substantial responsibility, to
     provide additional incentives to Employees and Consultants of the
     Corporation and its Subsidiaries, and to promote the success of the
     Corporation's business.  Options granted under this Plan may be incentive
     stock options (as defined under Section 422 of the Code) or nonstatutory
     stock options, as determined by the Administrator at the time of grant of
     an option and subject to the applicable provisions of Section 422 of the
     Code, as amended, and the regulations promulgated thereunder.

2.   Definitions.  As used in this Plan, the following definitions will apply:
     -----------

     (a)  Administrator.  The Board or any of its Committees.
          -------------

     (b)  Board. The Board of Directors of the Corporation.
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     (c)  Code.  The Internal Revenue Code of 1986, as amended.
          -----

     (d)  Committee.  A Committee appointed by the Board of Directors under
          ---------
          Section 4.

     (e)  Common Stock.  The Common Stock of the Corporation.
          ------------

     (f)  Corporation.  Objective Systems Integrators, Inc., a Delaware
          -----------
          corporation.

     (g)  Consultant.  Any director of the Corporation, a Parent or Subsidiary,
          ----------
          whether or not compensated for such services, and any person who is
          engaged by the Corporation, a Parent or Subsidiary to render
          consulting or advisory services and is compensated for those services.

     (h)  Continuous Status as an Employee or Consultant.   The employment,
          ----------------------------------------------
          directorship or consulting relationship with the Corporation, any
          Parent, or Subsidiary, has not been interrupted or ended.  Continuous
          Status will not be considered interrupted in the case of (1) a leave
          of absence approved by the Corporation, or (2) transfers between
          locations of the Corporation or between the Corporation, its Parent,
          any Subsidiary, or any successor.  Leaves of absence "approved by the
          Corporation" are those that have been properly approved by an
          authorized representative of the Corporation.  For Incentive Stock
          Options, no leave may exceed 90 days unless reemployment is guaranteed
          at the end of the leave by statute or contract, including Corporation
          policies.  If reemployment is not guaranteed, then on the 91st day of
          the leave Incentive Stock Options held by the Optionee will cease to
          be treated as an Incentive Stock Option and will be treated for tax
          purposes as a Nonstatutory Stock Option.

     (i)  Employee.  Any person, including Officers and directors, employed by
          --------
          the Corporation or any Parent or Subsidiary of the Corporation.  The
          payment of a director's fee by the Corporation is not sufficient to
          constitute "employment" by the Corporation.

     (j)  Exchange Act.  The Securities Exchange Act of 1934, as amended.
          ------------

     (k)  Fair Market Value.  As of any date, the value of Common Stock
          -----------------
          determined as follows:

          (i)  If the Common Stock is listed on an established stock exchange or
               a national market system, its Fair Market Value will be the
               closing sales price for the stock (or the closing bid, if no
               sales were reported) as quoted on the exchange or system for the
               last market trading day before the time of determination, as
               reported in The Wall Street Journal or such other source as the
               Administrator deems reliable;

          (ii) If the Common Stock is quoted on the NASDAQ System (but not on
               its Nasdaq National Market) or regularly quoted by a recognized
               securities dealer but selling prices are not

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                reported, its Fair Market Value will be the mean between the
                high bid and low asked prices for the Common Stock on the last
                market trading day before the day of determination, or;

          (iii) In the absence of an established market for the Common Stock,
                Fair Market Value will be determined in good faith by the
                Administrator.

     (l)  Incentive Stock Option.  An Option intended to qualify as an incentive
          ----------------------
          stock option within the meaning of Section 422 of the Code.

     (m)  Nonstatutory Stock Option.  An Option not intended to qualify as an
          -------------------------
          Incentive Stock Option.

     (n)  Officer.  A person who is an officer of the Corporation within the
          -------
          meaning of Section 16 of the Exchange Act and the rules and
          regulations promulgated thereunder.

     (o)  Option.  A stock option granted under the Plan.
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     (p)  Optioned Stock.  The Common Stock subject to an Option.
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     (q)  Optionee.  An Employee or Consultant who receives an Option.
          --------

     (r)  Parent.  A "parent corporation", whether now or hereafter existing, as
          ------
          defined in Section 424(e) of the Code.

     (s)  Plan.  This 1994 Stock Option Plan.
          ----

     (t)  Share.  A share of the Common Stock, as adjusted in accordance with
          -----
          Section 11.

     (u)  Subsidiary.  A "subsidiary corporation", whether now or hereafter
          ----------
          existing, as defined in Section 424(f) of the Code.

3.   Stock Subject to the Plan.  Subject to Section 11, the maximum aggregate
     -------------------------
     number of Shares which may be optioned and sold under the Plan is
     10,434,830 Shares.  The Shares may be authorized, but unissued, or
     reacquired Common Stock.

     If an Option expires or becomes unexercisable without having been exercised
     in full, or is surrendered under an Option Exchange Program, the
     unpurchased Shares will become available for future grant or sale under the
     Plan unless the Plan has terminated; provided, however, that Shares that
     have actually been issued under the Plan will not be returned to the Plan
     and will not become available for future distribution, except that if
     unvested Shares are repurchased by the Corporation at their original
     purchase price, and the original purchaser of those Shares did not receive
     any benefits of ownership of the Shares, the Shares will become available
     for future grant under the Plan.  For purposes of the preceding sentence,
     voting rights are not considered a benefit of Share ownership.

4.   Administration of the Plan.
     --------------------------

     (a)  Plan Procedures.
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          (1)  Administration for Directors and Officers.  For Options to
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               Employees who are also Officers or directors of the Corporation,
               the Plan will be administered by (A) the Board if the Board can
               administer it in compliance with Rule 16b-3 under the Exchange
               Act or any successor thereto ("Rule 16b-3") for plans intended to
               qualify as discretionary, or (B) a Committee designated by the
               Board, which Committee will be constituted to permit the Plan to
               comply with Rule 16b-3 for plans intended to qualify as
               discretionary.  Once appointed, this Committee will continue to
               serve in its designated capacity until otherwise directed by the
               Board.  From time to time the Board may increase the size of the
               Committee, appoint additional members of the Committee, remove
               members (with or without cause), appoint new members in
               substitution for removed members, fill vacancies, however caused,
               and remove all members and thereafter directly administer the
               Plan, all to the extent permitted by Rule 16b-3 for plans
               intended to qualify as discretionary plans.

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          (2)  Multiple Administrative Bodies.  If permitted by Rule 16b-3, the
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               Plan may be administered by different bodies with respect to
               directors, non-director Officers and Employees who are neither
               directors nor Officers.

          (3)  Administration for Consultants and Other Employees.  For Options
               --------------------------------------------------
               to Employees or Consultants who are neither directors nor
               Officers of the Corporation, the Plan will be administered by (A)
               the Board, or (B) a committee designated by the Board, which will
               be constituted to satisfy the legal requirements relating to the
               administration of incentive stock option plans, if any, of
               Delaware corporate and securities laws, of the Code, and of any
               applicable stock exchange ("Applicable Laws").  Once appointed,
               this Committee will continue to serve in its designated capacity
               until otherwise directed by the Board.  From time to time the
               Board may increase the size of the Committee, appoint additional
               members of the Committee, remove members (with or without cause),
               appoint new members in substitution for removed members, fill
               vacancies, however caused, and remove all members and thereafter
               directly administer the Plan, all to the extent permitted by the
               Applicable Laws.

     (b)  Powers of the Administrator.  Subject to the provisions of the Plan
          ---------------------------
          and, in the case of a Committee, the specific duties delegated by the
          Board to the Committee, and subject to the approval of any relevant
          authorities including, if required, the approval of any stock exchange
          on which the Common Stock is listed, the Administrator will have the
          authority, in its discretion:

          (1)  to determine the Fair Market Value of the Common Stock;

          (2)  to select the Consultants and Employees to whom Options may be
               granted;

          (3)  to determine whether and to what extent Options are granted;

          (4)  to determine the number of shares of Common Stock to be covered
               by each Option;

          (5)  to approve forms of written agreement for use under the Plan
               ("Option Agreement");

          (6)  to determine the terms and conditions of any Option;

          (7)  to determine whether and under what circumstances an Option may
               be settled in cash under subsection 9(f) instead of Common Stock;

          (8)  to reduce the exercise price of any Option to the then current
               Fair Market Value if the Fair Market Value of the Common Stock
               covered by the Option has declined since the date the Option was
               granted; and

          (9)  to construe and interpret the terms of the Plan and Options
               granted under it.

     (c)  Effect of Administrator's Decision.  All decisions, determinations and
          ----------------------------------
          interpretations of the Administrator will be final and binding on all
          Optionees and any other holders of an Option.

5.   Eligibility.
     -----------

     (a)  Type of Option.  Nonstatutory Stock Options may be granted to
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          Employees and Consultants.  Incentive Stock Options may be granted
          only to Employees and Consultants who are directors. An Employee or
          Consultant who has been granted an Option may, if otherwise eligible,
          be granted additional Options.

     (b)  Option Terms.  Each Option will be designated in the Option Agreement
          ------------
          as either an Incentive Stock Option or a Nonstatutory Stock Option.
          However, notwithstanding that designation, to the extent the aggregate
          Fair Market Value:

          (1)  of Shares subject to an Optionee's Incentive Stock Options
               granted by the Corporation, any Parent or Subsidiary, which

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          (2)  become exercisable for the first time during any calendar year
               (under all plans of the Corporation or any Parent or Subsidiary)
               exceeds $100,000, the excess Options will be treated as
               Nonstatutory Stock Options.  For purposes of this Section,
               Incentive Stock Options will be taken into account in the order
               in which they were granted, and the Fair Market Value of the
               Shares will be determined at time the Option is granted.

     (c)  At Will Employment.  The Plan does not confer on an Optionee any
          ------------------
          rights regarding continuation of an employment or consulting
          relationship with the Corporation, nor will it interfere in any way
          with the Optionee's or the Corporation's right to terminate the
          Optionee's employment or consulting relationship at any time, with or
          without cause.

     (d)  Limitations.  If the Corporation or a successor corporation issues any
          -----------
          class of common equity securities required to be registered under
          Section 12 of the Exchange Act, or if the Plan is assumed by a
          corporation having a class of common equity securities required to be
          registered under Section 12 of the Exchange Act, the following
          limitations will apply to grants of Options to Employees:

          (1)  No Employee will be granted, in any fiscal year of the
               Corporation, Options to purchase more than 1,375,000 Shares.

          (2)  This limitation will be adjusted proportionately in connection
               with any change in the Corporation's capitalization as described
               in Section 11.

          (3)  If an Option is canceled in the same fiscal year of the
               Corporation in which it was granted (other than in connection
               with a transaction described in Section 11), the cancelled Option
               will be counted against the limits in this Section 5.  For this
               purpose, if the exercise price of an Option is reduced, the
               transaction will be treated as a cancellation of the Option and
               the grant of a new Option.

6.   Term of Plan.  The Plan will become effective on the earlier to occur of
     ------------
     its adoption by the Board or its approval by the Corporation's
     shareholders, as described in Section 17.  It will continue in effect for a
     term of 10 years unless sooner terminated under Section 13.

7.   Term of Option.  The term of each Option will be the term stated in the
     --------------
     Option Agreement; provided, however, that the term will be no more than 10
     years from the date of grant.  For Incentive Stock Options granted to an
     Optionee who, at the time of the grant, owns stock representing more than
     10% of the voting power of all classes of stock of the Corporation or any
     Parent or Subsidiary, the term of the Option will be five years from the
     date of grant or such shorter term as may be provided in the Option
     Agreement.

8.   Exercise Price and Consideration.
     --------------------------------

     (a)  Price.  The per Share exercise price for Shares to be issued on
          -----
          exercise of an Option will be the price determined by the Board, but
          will be subject to the following:

          (1)  In the case of an Incentive Stock Option

               (A)  granted to an Employee who, at the time of the grant, owns
                    stock representing more than 10% of the voting power of all
                    classes of stock of the Corporation or any Parent or
                    Subsidiary, the per Share exercise price not be less than
                    110% of the Fair Market Value per Share on the date of
                    grant.

               (B)  granted to any Employee other than an Employee described in
                    the preceding paragraph, the per Share exercise price will
                    not be less than 100% of the Fair Market Value per Share on
                    the date of grant.

          (2)  In the case of a Nonstatutory Stock Option

               (A)  granted to a person who, at the time of the grant, owns
                    stock representing more than 10% of the voting power of all
                    classes of stock of the Corporation or any Parent or
                    Subsidiary, the per Share exercise price will not be less
                    than 110% of the Fair Market Value per Share on the date of
                    the grant.

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               (B)  granted to any person, the per Share exercise price will not
                    be less than 85% of the Fair Market Value per Share on the
                    date of grant.

     (b)  The consideration to be paid for the Shares issued on exercise of an
          Option, including the method of payment, will be determined by the
          Administrator (and, in the case of an Incentive Stock Option, will be
          determined at the time of grant) and may consist entirely of (1) cash,
          (2) check, (3) promissory note, (4) other Shares which (x) in the case
          of Shares acquired on exercise of an Option have been owned by the
          Optionee for more than six months on the date of surrender, and (y)
          have a Fair Market Value on the date of surrender equal to the
          aggregate exercise price of the Shares as to which the Option will be
          exercised, (5) delivery of a properly executed exercise notice
          together with such other documentation as the Administrator and the
          broker, if applicable, require to effect an exercise of the Option and
          delivery to the Corporation of the sale or loan proceeds required to
          pay the exercise price, or (6) any combination of the foregoing
          methods of payment.  In making its determination, the Board will
          consider whether the type of consideration may reasonably be expected
          to benefit the Corporation.

9.   Exercise of Option.
     ------------------

     (a)  Procedure for Exercise; Rights as a Shareholder.  Options granted
          -----------------------------------------------
          under the Plan will be exercisable at such times and under such
          conditions as determined by the Board, including performance criteria
          with respect to the Corporation and/or the Optionee, and as will be
          permissible under the terms of the Plan, but in no case at a rate of
          less than 20% per year over five years from the date the Option is
          granted.

          An Option may not be exercised for a fraction of a Share.

          An Option will be deemed to have been exercised when (a) written
          notice of exercise has been given to the Corporation in accordance
          with the terms of the Option and by the person entitled to exercise
          it, and (b) full payment for the Shares has been received by the
          Corporation.  Full payment may, as authorized by the Board, consist of
          any consideration and method of payment allowable under Section 8(b).
          Notwithstanding exercise of an Option, no right to vote or receive
          dividends or any other rights as a shareholder will exist with respect
          to Optioned Stock until a stock certificate for the Shares has been
          issued, as evidenced by the appropriate entry on the books of the
          Corporation or of a duly authorized transfer agent of the Corporation.
          The Corporation will issue (or cause to be issued) a stock certificate
          promptly after exercise of the Option.  Except as provided in Section
          11, no adjustment will be made for a dividend or other right for which
          the record date is before the date the stock certificate is issued.

          Exercise of an Option will result in a decrease in the number of
          Shares that are thereafter available, both for purposes of the Plan
          and for sale under the Option, by the number of Shares as to which the
          Option is exercised.

     (b)  Termination of Relationship.   If an Optionee's Continuous Status as
          ---------------------------
          an Employee or Consultant ends (but not if there is a change in status
          from Employee to Consultant (in which case an Employee's Incentive
          Stock Option will automatically convert to a Nonstatutory Stock Option
          on the 91st day after the change of status) or from Consultant to
          Employee), the Optionee may, but only within such period as is
          determined by the Administrator (which will be at least 30 days and,
          in the case of an Incentive Stock Option, will not exceed three months
          after the date the Continuous Status as an Employee or Consultant ends
          but in no event later than the expiration date of the Option set forth
          in the Option Agreement) exercise the Option to the extent that the
          Optionee was entitled to exercise it on the date Continuous Status as
          an Employee or Consultant ends. To the extent an Optionee was not
          entitled to exercise the Option on the date Continuous Status as an
          Employee or Consultant ends, or if Optionee does not exercise the
          Option within the time specified, the Option will terminate.

     (c)  Disability.  If an Optionee's consulting relationship or Continuous
          ----------
          Status as an Employee ends as a result of the Optionee's disability,
          the Optionee may, but only within 12 months from the date of
          termination (and in no event later than the expiration date of the
          Option set forth in the Option Agreement), exercise the Option to the
          extent otherwise entitled to exercise it on the date of termination;
          provided, however, that if the disability is not a "disability" as
          defined in Section

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          22(e)(3) of the Code, in the case of an Incentive Stock Option the
          Incentive Stock Option will automatically convert to a Nonstatutory
          Stock Option three months and one day after termination. To the extent
          that the Optionee is not entitled to exercise the Option on the date
          of termination, or if the Optionee does not exercise the Option to the
          extent so entitled within the time specified, the Option will
          terminate and the Shares covered by the Option will revert to the
          Plan.

     (d)  Death.  If an Optionee dies, the Option may be exercised at any time
          -----
          within 12 months after the date of death (but in no event later than
          the expiration of the Option set forth in the Notice of Grant), by the
          Optionee's estate or by a person who acquired the right to exercise
          the Option by bequest or inheritance, but only to the extent that the
          Optionee was entitled to exercise the Option on the date of death.
          If, at the time of death, the Optionee was not entitled to exercise
          the entire Option, the Shares covered by the unexercisable part of the
          Option will immediately revert to the Plan.  If, after death, the
          Optionee's estate or the person who acquired the right to exercise the
          Option by bequest or inheritance does not exercise the Option within
          the time specified, the Option will terminate and the Shares covered
          by the Option will revert to the Plan.

     (e)  Rule 16b-3.  Options granted to individuals subject to Section 16(b)
          ----------
          of the Exchange Act will comply with Rule 16b-3 and will contain such
          additional conditions or restrictions as may be required thereunder to
          qualify for the maximum exemption from Section 16 of the Exchange Act
          for Plan transactions.

     (f)  Buyout Provisions.  At any time, the Administrator may offer to buy
          -----------------
          out (for a payment in cash or Shares) an Option previously granted.
          The offer may be based on such terms and conditions as the
          Administrator establishes and communicates to the Optionee at the time
          the offer is made.

10.  Non-Transferability.  Options may not be sold, pledged, assigned,
     --------------------
     hypothecated, transferred, or disposed of in any manner other than by will
     or by the laws of descent or distribution and may be exercised, during the
     lifetime of the Optionee, only by the Optionee.

11.  Adjustments on Changes in Capitalization or Merger.
     --------------------------------------------------

     (a)  Changes in Capitalization.  Subject to any required action by the
          -------------------------
          Corporation's shareholders, the number of shares of Common Stock
          covered by each outstanding Option, and the number of shares of Common
          Stock which have been authorized for issuance under the Plan but as to
          which no Options have yet been granted or which have been returned to
          the Plan upon cancellation or expiration of an Option, as well as the
          price per share of Common Stock covered by each outstanding Option,
          will be proportionately adjusted for any increase or decrease in the
          number of issued shares of Common Stock resulting from a stock split,
          reverse stock split, stock dividend, combination or reclassification
          of the Common Stock, or any other increase or decrease in the number
          of issued shares of Common Stock effected without receipt of
          consideration by the Corporation; provided, however, that conversion
          of any convertible securities of the Corporation will not be deemed to
          have been "effected without receipt of consideration."  This
          adjustment will be made by the Board, whose determination will be
          final, binding and conclusive.  Except as expressly provided in the
          Plan, the Corporation's issuance of shares of stock of any class, or
          securities convertible into shares of stock of any class, will not
          affect, and no adjustment by reason thereof will be made with respect
          to, the number or price of shares of Common Stock subject to an
          Option.

     (b)  Dissolution or Liquidation.  If there is a proposed dissolution or
          --------------------------
          liquidation of the Corporation, the Board will notify the Optionee at
          least 15 days before the proposed action.  To the extent it has not
          been previously exercised, the Option will end immediately before the
          consummation of the proposed action.

     (c)  Merger.  If the Corporation is merged with or into another
          ------
          corporation, the Option may be assumed or an equivalent option may be
          substituted by the successor corporation or a parent or subsidiary of
          the successor corporation.  If, the Option is not assumed or
          substituted, the Option will end as of the date the merger is closed.
          For the purposes of this paragraph, an Option will be considered
          "assumed" if, after the merger, it confers the right to purchase, for
          each Share of Optioned Stock immediately before the merger, the same
          consideration (whether stock, cash, or other securities or property)
          received in the merger by holders of Common Stock for each Share held
          by the holders of Common Stock on the effective date of the
          transaction (and if the holders of Common Stock were

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          offered a choice of consideration, the type of consideration chosen by
          the holders of a majority of the outstanding Shares); provided,
          however, that if the consideration received in the merger was not
          solely common stock of the successor corporation or its Parent, the
          Administrator may, with the consent of the successor corporation,
          provide that the consideration to be received on the exercise of an
          Option for each Share of Optioned Stock to be solely an amount of
          common stock of the successor corporation or its Parent that is equal
          in fair market value to the per share consideration received by
          holders of Common Stock in the merger.

12.  Time of Granting Options.  The date of an Option grant will be the date on
     ------------------------
     which the Administrator decides to grant the Option, or such other date as
     is determined by the Board.  Notice of the decision will be given to each
     Employee or Consultant to whom an Option is granted within a reasonable
     time after the date of grant.

13.  Amendment and Termination of the Plan.
     -------------------------------------

     (a)  Amendment and Termination.  The Board may at any time amend, alter,
          -------------------------
          suspend or discontinue the Plan, but without the Optionee's consent no
          amendment, alteration, suspension or discontinuation will be made
          which would impair the rights of the Optionee under any grant
          previously made.  In addition, to the extent necessary or desirable to
          comply with Rule 16b-3 under the Exchange Act or with Section 422 of
          the Code (or any other applicable law or regulation, including the
          requirements of the NASD or an established stock exchange), the
          Corporation will obtain shareholder approval of any Plan amendment in
          such a manner and to such a degree as required.

     (b)  Effect of Amendment or Termination.   An amendment or termination of
          ----------------------------------
          the Plan will not affect Options that have already been granted.
          Previously granted Options will remain in full force and effect as if
          the Plan had not been amended or terminated, unless mutually agreed
          otherwise by the Optionee and the Board in a written agreement signed
          by the Optionee and the Corporation.

14.  Conditions on Issuance of Shares.   Shares will not be issued on exercise
     --------------------------------
     of an Option unless the exercise of the Option and the issuance and
     delivery of the Shares (a) complies with all relevant provisions of law,
     including, without limitation, the Securities Act of 1933, as amended, the
     Exchange Act, the rules and regulations promulgated thereunder, and the
     requirements of any stock exchange on which the Shares are then listed, and
     (b) has been approved by counsel for the Corporation with respect to such
     compliance.

     As a condition of exercising an Option, the Corporation may require the
     person exercising it to represent and warrant at the time of exercise that
     the Shares are being purchased only for investment and without any present
     intention to sell or distribute them if, in the opinion of counsel for the
     Corporation, such a representation is legally required.

15.  Reservation of Shares.  During the term of the Plan, the Corporation will
     ---------------------
     reserve and keep available a number of Shares that are sufficient to
     satisfy the requirements of the Plan.

     The inability of the Corporation to obtain authority from any regulatory
     body having jurisdiction, which authority the Corporation's counsel deems
     to be necessary to the lawful issuance and sale of any Shares under the
     Plan, will relieve the Corporation of liability for not issuing or selling
     those Shares.

16.  Agreements.  Options will be evidenced by written agreements in such form
     ----------
     as the Board from time to time approves.

17.  Shareholder Approval.  Continuance of the Plan will be subject to approval
     --------------------
     by the Corporation's shareholders within 12 months before or after the date
     the Plan is adopted.  Shareholder approval will be obtained in the degree
     and manner required under applicable state and federal law and the rules of
     any stock exchange on which the Common Stock is listed.

18.  Information to Optionees and Purchasers.  The Corporation will provide each
     ---------------------------------------
     Optionee, not less frequently than annually, with copies of annual
     financial statements.  The Corporation will also provide financial
     statements to each individual who acquires Shares under the Plan while the
     individual owns the Shares.  The Corporation will not be required to
     provide such statements to key employees whose duties in connection with
     the Corporation assure their access to equivalent information.

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