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                                                                   EXHIBIT 10.6

                            KABIRA TECHNOLOGIES, INC.

                                 2000 STOCK PLAN


      1. Purposes of the Plan. The purposes of this 2000 Stock Plan are:

            -     to attract and retain the best available personnel for
                  positions of substantial responsibility,

            -     to provide additional incentive to Employees, Directors and
                  Consultants, and

            -     to promote the success of the Company's business.

            Options granted under the Plan may be Incentive Stock Options or
Nonstatutory Stock Options, as determined by the Administrator at the time of
grant. Stock Purchase Rights may also be granted under the Plan.

      2. Definitions. As used herein, the following definitions shall apply:

            (a) "Administrator" means the Board or any of its Committees as
shall be administering the Plan, in accordance with Section 4 of the Plan.

            (b) "Applicable Laws" means the requirements relating to the
administration of stock option plans under U. S. state corporate laws, U.S.
federal and state securities laws, the Code, any stock exchange or quotation
system on which the Common Stock is listed or quoted and the applicable laws of
any foreign country or jurisdiction where Options or Stock Purchase Rights are,
or will be, granted under the Plan.

            (c) "Board" means the Board of Directors of the Company.

            (d) "Code" means the Internal Revenue Code of 1986, as amended.

            (e) "Committee" means a committee of Directors appointed by the
Board in accordance with Section 4 of the Plan.

            (f) "Common Stock" means the common stock of the Company.

            (g) "Company" means Kabira Technologies, Inc., a Delaware
corporation.

            (h) "Consultant" means any person, including an advisor, engaged by
the Company or a Parent or Subsidiary to render services to such entity.

            (i) "Director" means a member of the Board.

            (j) "Disability" means total and permanent disability as defined in
Section 22(e)(3) of the Code.

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            (k) "Employee" means any person, including Officers and Directors,
employed by the Company or any Parent or Subsidiary of the Company. A Service
Provider shall not cease to be an Employee in the case of (i) any leave of
absence approved by the Company or (ii) transfers between locations of the
Company or between the Company, its Parent, any Subsidiary, or any successor.
For purposes of Incentive Stock Options, no such leave may exceed ninety days,
unless reemployment upon expiration of such leave is guaranteed by statute or
contract. If reemployment upon expiration of a leave of absence approved by the
Company is not so guaranteed, on the 181st day of such leave any Incentive Stock
Option held by the Optionee shall cease to be treated as an Incentive Stock
Option and shall be treated for tax purposes as a Nonstatutory Stock Option.
Neither service as a Director nor payment of a director's fee by the Company
shall be sufficient to constitute "employment" by the Company.

            (l) "Exchange Act" means the Securities Exchange Act of 1934, as
amended.

            (m) "Fair Market Value" means, as of any date, the value of Common
Stock determined as follows:

                     (i) If the Common Stock is listed on any established stock
exchange or a national market system, including without limitation the Nasdaq
National Market or The Nasdaq SmallCap Market of The Nasdaq Stock Market, its
Fair Market Value shall be the closing sales price for such stock (or the
closing bid, if no sales were reported) as quoted on such exchange or system for
the last market trading day prior to 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 regularly quoted by a
recognized securities dealer but selling prices are not reported, the Fair
Market Value of a Share of Common Stock shall be the mean between the high bid
and low asked prices for the Common Stock on the last market trading day prior
to the day of determination, as reported in The Wall Street Journal or such
other source as the Administrator deems reliable; or

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

            (n) "Incentive Stock Option" means an Option intended to qualify as
an incentive stock option within the meaning of Section 422 of the Code and the
regulations promulgated thereunder.

            (o) "Nonstatutory Stock Option" means an Option not intended to
qualify as an Incentive Stock Option.

            (p) "Notice of Grant" means a written or electronic notice
evidencing certain terms and conditions of an individual Option or Stock
Purchase Right grant. The Notice of Grant is part of the Option Agreement.

            (q) "Officer" means a person who is an officer of the Company within
the meaning of Section 16 of the Exchange Act and the rules and regulations
promulgated thereunder.

            (r) "Option" means a stock option granted pursuant to the Plan.


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            (s) "Option Agreement" means an agreement between the Company and an
Optionee evidencing the terms and conditions of an individual Option grant. The
Option Agreement is subject to the terms and conditions of the Plan.

            (t) "Option Exchange Program" means a program whereby outstanding
Options are surrendered in exchange for Options with a lower exercise price.

            (u) "Optioned Stock" means the Common Stock subject to an Option or
Stock Purchase Right.

            (v) "Optionee" means the holder of an outstanding Option or Stock
Purchase Right granted under the Plan.

            (w) "Parent" means a "parent corporation," whether now or hereafter
existing, as defined in Section 424(e) of the Code.

            (x) "Plan" means this Kabira Technologies, Inc. 2000 Stock Plan.

            (y) "Restricted Stock" means shares of Common Stock acquired
pursuant to a grant of Stock Purchase Rights under Section 11 of the Plan.

            (z) "Restricted Stock Purchase Agreement" means a written agreement
between the Company and the Optionee evidencing the terms and restrictions
applying to stock purchased under a Stock Purchase Right. The Restricted Stock
Purchase Agreement is subject to the terms and conditions of the Plan and the
Notice of Grant.

            (aa) "Rule 16b-3" means Rule 16b-3 of the Exchange Act or any
successor to Rule 16b-3, as in effect when discretion is being exercised with
respect to the Plan.

            (bb) "Section 16(b) " means Section 16(b) of the Exchange Act.

            (cc) "Service Provider" means an Employee, Director or Consultant.

            (dd) "Share" means a share of the Common Stock, as adjusted in
accordance with Section 13 of the Plan.

            (ee) "Stock Purchase Right" means the right to purchase Common Stock
pursuant to Section 11 of the Plan, as evidenced by a Notice of Grant.

            (ff) "Subsidiary" means 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 the provisions of Section 13 of
the Plan, the maximum aggregate number of Shares that may be optioned and sold
under the Plan is 4,000,000 Shares, plus an annual increase to be added on the
first day of the Company's fiscal year, beginning in 2001, equal to the least of
(i) 4,000,000 shares, (ii) 6% of the outstanding shares on such date, and (iii)
a lesser amount determined by the Board. The Shares may be authorized, but
unissued, or reacquired Common Stock.


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            If an Option or Stock Purchase Right expires or becomes
unexercisable without having been exercised in full, or is surrendered pursuant
to an Option Exchange Program, the unpurchased Shares which were subject thereto
shall 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, whether upon exercise of an Option or Right, shall not be
returned to the Plan and shall not become available for future distribution
under the Plan, except that if Shares of Restricted Stock are repurchased by the
Company at their original purchase price, such Shares shall become available for
future grant under the Plan.

      4. Administration of the Plan.

            (a) Procedure.

                     (i) Multiple Administrative Bodies. Different Committees
with respect to different groups of Service Providers may administer the Plan.

                     (ii) Section 162(m). To the extent that the Administrator
determines it to be desirable to qualify Options granted hereunder as
"performance-based compensation" within the meaning of Section 162(m) of the
Code, the Plan shall be administered by a Committee of two or more "outside
directors" within the meaning of Section 162(m) of the Code.

                     (iii) Rule 16b-3. To the extent desirable to qualify
transactions hereunder as exempt under Rule 16b-3, the transactions contemplated
hereunder shall be structured to satisfy the requirements for exemption under
Rule 16b-3.

                     (iv) Other Administration. Other than as provided above,
the Plan shall be administered by (A) the Board or (B) a Committee, which
committee shall be constituted to satisfy Applicable Laws.

            (b) Powers of the Administrator. Subject to the provisions of the
Plan, and in the case of a Committee, subject to the specific duties delegated
by the Board to such Committee, the Administrator shall have the authority, in
its discretion:

                     (i) to determine the Fair Market Value;

                     (ii) to select the Service Providers to whom Options and
Stock Purchase Rights may be granted hereunder;

                     (iii) to determine the number of shares of Common Stock to
be covered by each Option and Stock Purchase Right granted hereunder;

                     (iv) to approve forms of agreement for use under the Plan;

                     (v) to determine the terms and conditions, not inconsistent
with the terms of the Plan, of any Option or Stock Purchase Right granted
hereunder. Such terms and conditions include, but are not limited to, the
exercise price, the time or times when Options or Stock Purchase Rights may be
exercised (which may be based on performance criteria), any vesting acceleration
or waiver of forfeiture restrictions, and any restriction or limitation
regarding any Option or Stock


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Purchase Right or the shares of Common Stock relating thereto, based in each
case on such factors as the Administrator, in its sole discretion, shall
determine;

                     (vi) to reduce the exercise price of
any Option or Stock Purchase Right to the then current Fair Market Value if the
Fair Market Value of the Common Stock covered by such Option or Stock Purchase
Right shall have declined since the date the Option or Stock Purchase Right was
granted;

                     (vii) to institute an Option Exchange Program;

                     (viii) to construe and interpret the terms of the Plan and
awards granted pursuant to the Plan;

                     (ix) to prescribe, amend and rescind rules and regulations
relating to the Plan, including rules and regulations relating to sub-plans
established for the purpose of qualifying for preferred tax treatment under
foreign tax laws;

                     (x) to modify or amend each Option or Stock Purchase Right
(subject to Section 15(c) of the Plan), including the discretionary authority to
extend the post-termination exercisability period of Options longer than is
otherwise provided for in the Plan;

                     (xi) to allow Optionees to satisfy withholding tax
obligations by electing to have the Company withhold from the Shares to be
issued upon exercise of an Option or Stock Purchase Right that number of Shares
having a Fair Market Value equal to the amount required to be withheld. The Fair
Market Value of the Shares to be withheld shall be determined on the date that
the amount of tax to be withheld is to be determined. All elections by an
Optionee to have Shares withheld for this purpose shall be made in such form and
under such conditions as the Administrator may deem necessary or advisable;

                     (xii) to authorize any person to execute on behalf of the
Company any instrument required to effect the grant of an Option or Stock
Purchase Right previously granted by the Administrator;

                     (xiii) to make all other determinations deemed necessary or
advisable for administering the Plan.

            (c) Effect of Administrator's Decision. The Administrator's
decisions, determinations and interpretations shall be final and binding on all
Optionees and any other holders of Options or Stock Purchase Rights.

      5. Eligibility. Nonstatutory Stock Options and Stock Purchase Rights may
be granted to Service Providers. Incentive Stock Options may be granted only to
Employees.

      6. Limitations.

            (a) Each Option shall be designated in the Option Agreement as
either an Incentive Stock Option or a Nonstatutory Stock Option. However,
notwithstanding such designation, to the extent that the aggregate Fair Market
Value of the Shares with respect to which


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Incentive Stock Options are exercisable for the first time by the Optionee
during any calendar year (under all plans of the Company and any Parent or
Subsidiary) exceeds $100,000, such Options shall be treated as Nonstatutory
Stock Options. For purposes of this Section 6(a), Incentive Stock Options shall
be taken into account in the order in which they were granted. The Fair Market
Value of the Shares shall be determined as of the time the Option with respect
to such Shares is granted.

            (b) Neither the Plan nor any Option or Stock Purchase Right shall
confer upon an Optionee any right with respect to continuing the Optionee's
relationship as a Service Provider with the Company, nor shall they interfere in
any way with the Optionee's right or the Company's right to terminate such
relationship at any time, with or without cause.

            (c) The following limitations shall apply to grants of Options:

                     (i) No Service Provider shall be granted, in any fiscal
year of the Company, Options to purchase more than 1,000,000 Shares.

                     (ii) In connection with his or her initial service, a
Service Provider may be granted Options to purchase up to an additional
1,000,000 Shares, which shall not count against the limit set forth in
subsection (i) above.

                     (iii) The foregoing limitations shall be adjusted
proportionately in connection with any change in the Company's capitalization as
described in Section 13.

                     (iv) If an Option is cancelled in the same fiscal year of
the Company in which it was granted (other than in connection with a transaction
described in Section 13), the cancelled Option will be counted against the
limits set forth in subsections (i) and (ii) above. 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.

      7. Term of Plan. Subject to Section 19 of the Plan, the Plan shall become
effective upon its adoption by the Board. It shall continue in effect for a term
of ten (10) years unless terminated earlier under Section 15 of the Plan.

      8. Term of Option. The term of each Option shall be stated in the Option
Agreement. In the case of an Incentive Stock Option, the term shall be ten (10)
years from the date of grant or such shorter term as may be provided in the
Option Agreement. Moreover, in the case of an Incentive Stock Option granted to
an Optionee who, at the time the Incentive Stock Option is granted, owns stock
representing more than ten percent (10%) of the total combined voting power of
all classes of stock of the Company or any Parent or Subsidiary, the term of the
Incentive Stock Option shall be five (5) years from the date of grant or such
shorter term as may be provided in the Option Agreement.

      9. Option Exercise Price and Consideration.

            (a) Exercise Price. The per share exercise price for the Shares to
be issued pursuant to exercise of an Option shall be determined by the
Administrator, subject to the following:

                     (i) In the case of an Incentive Stock Option


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                        (A) granted to an Employee who, at the time the
Incentive Stock Option is granted, owns stock representing more than ten percent
(10%) of the voting power of all classes of stock of the Company or any Parent
or Subsidiary, the per Share exercise price shall be no 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 paragraph (A) immediately above, the per Share exercise price shall
be no less than 100% of the Fair Market Value per Share on the date of grant.

                     (ii) In the case of a Nonstatutory Stock Option, the per
Share exercise price shall be determined by the Administrator. In the case of a
Nonstatutory Stock Option intended to qualify as "performance-based
compensation" within the meaning of Section 162(m) of the Code, the per Share
exercise price shall be no less than 100% of the Fair Market Value per Share on
the date of grant.

                     (iii) Notwithstanding the foregoing, Options may be granted
with a per Share exercise price of less than 100% of the Fair Market Value per
Share on the date of grant pursuant to a merger or other corporate transaction.

            (b) Waiting Period and Exercise Dates. At the time an Option is
granted, the Administrator shall fix the period within which the Option may be
exercised and shall determine any conditions that must be satisfied before the
Option may be exercised.

            (c) Form of Consideration. The Administrator shall determine the
acceptable form of consideration for exercising an Option, including the method
of payment. In the case of an Incentive Stock Option, the Administrator shall
determine the acceptable form of consideration at the time of grant. Such
consideration may consist entirely of:

                     (i) cash;

                     (ii) check;

                     (iii) promissory note;

                     (iv) other Shares which (A) in the case of Shares acquired
upon exercise of an option, have been owned by the Optionee for more than six
months on the date of surrender, and (B) have a Fair Market Value on the date of
surrender equal to the aggregate exercise price of the Shares as to which said
Option shall be exercised;

                     (v) consideration received by the Company under a cashless
exercise program implemented by the Company in connection with the Plan;

                     (vi) a reduction in the amount of any Company liability to
the Optionee, including any liability attributable to the Optionee's
participation in any Company-sponsored deferred compensation program or
arrangement;

                     (vii) any combination of the foregoing methods of payment;
or


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                     (viii) such other consideration and method of payment for
the issuance of Shares to the extent permitted by Applicable Laws.

      10. Exercise of Option.

            (a) Procedure for Exercise; Rights as a Stockholder. Any Option
granted hereunder shall be exercisable according to the terms of the Plan and at
such times and under such conditions as determined by the Administrator and set
forth in the Option Agreement. Unless the Administrator provides otherwise,
vesting of Options granted hereunder shall be tolled during any unpaid leave of
absence. An Option may not be exercised for a fraction of a Share.

                  An Option shall be deemed exercised when the Company receives:
(i) written or electronic notice of exercise (in accordance with the Option
Agreement) from the person entitled to exercise the Option, and (ii) full
payment for the Shares with respect to which the Option is exercised. Full
payment may consist of any consideration and method of payment authorized by the
Administrator and permitted by the Option Agreement and the Plan. Shares issued
upon exercise of an Option shall be issued in the name of the Optionee or, if
requested by the Optionee, in the name of the Optionee and his or her spouse.
Until the Shares are issued (as evidenced by the appropriate entry on the books
of the Company or of a duly authorized transfer agent of the Company), no right
to vote or receive dividends or any other rights as a stockholder shall exist
with respect to the Optioned Stock, notwithstanding the exercise of the Option.
The Company shall issue (or cause to be issued) such Shares promptly after the
Option is exercised. No adjustment will be made for a dividend or other right
for which the record date is prior to the date the Shares are issued, except as
provided in Section 13 of the Plan.

                  Exercising an Option in any manner shall decrease the number
of Shares 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 as a Service Provider. If an
Optionee ceases to be a Service Provider, other than upon the Optionee's death
or Disability, the Optionee may exercise his or her Option within such period of
time as is specified in the Option Agreement to the extent that the Option is
vested on the date of termination (but in no event later than the expiration of
the term of such Option as set forth in the Option Agreement). In the absence of
a specified time in the Option Agreement, the Option shall remain exercisable
for three (3) months following the Optionee's termination. If, on the date of
termination, the Optionee is not vested as to his or her entire Option, the
Shares covered by the unvested portion of the Option shall revert to the Plan.
If, after termination, the Optionee does not exercise his or her Option within
the time specified by the Administrator, the Option shall terminate, and the
Shares covered by such Option shall revert to the Plan.

            (c) Disability of Optionee. If an Optionee ceases to be a Service
Provider as a result of the Optionee's Disability, the Optionee may exercise his
or her Option within such period of time as is specified in the Option Agreement
to the extent the Option is vested on the date of termination (but in no event
later than the expiration of the term of such Option as set forth in the Option
Agreement). In the absence of a specified time in the Option Agreement, the
Option shall remain exercisable for twelve (12) months following the Optionee's
termination. If, on the date of


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termination, the Optionee is not vested as to his or her entire Option, the
Shares covered by the unvested portion of the Option shall revert to the Plan.
If, after termination, the Optionee does not exercise his or her Option within
the time specified herein, the Option shall terminate, and the Shares covered by
such Option shall revert to the Plan.

            (d) Death of Optionee. If an Optionee dies while a Service Provider,
the Option may be exercised within such period of time as is specified in the
Option Agreement (but in no event later than the expiration of the term of such
Option as set forth in the Notice of Grant), by the Optionee's estate or by a
person who acquires the right to exercise the Option by bequest or inheritance,
but only to the extent that the Option is vested on the date of death. In the
absence of a specified time in the Option Agreement, the Option shall remain
exercisable for twelve (12) months following the Optionee's termination. If, at
the time of death, the Optionee is not vested as to his or her entire Option,
the Shares covered by the unvested portion of the Option shall immediately
revert to the Plan. The Option may be exercised by the executor or administrator
of the Optionee's estate or, if none, by the person(s) entitled to exercise the
Option under the Optionee's will or the laws of descent or distribution. If the
Option is not so exercised within the time specified herein, the Option shall
terminate, and the Shares covered by such Option shall revert to the Plan.

            (e) Buyout Provisions. The Administrator may at any time offer to
buy out for a payment in cash or Shares an Option previously granted based on
such terms and conditions as the Administrator shall establish and communicate
to the Optionee at the time that such offer is made.

      11. Stock Purchase Rights.

            (a) Rights to Purchase. Stock Purchase Rights may be issued either
alone, in addition to, or in tandem with other awards granted under the Plan
and/or cash awards made outside of the Plan. After the Administrator determines
that it will offer Stock Purchase Rights under the Plan, it shall advise the
offeree in writing or electronically, by means of a Notice of Grant, of the
terms, conditions and restrictions related to the offer, including the number of
Shares that the offeree shall be entitled to purchase, the price to be paid, and
the time within which the offeree must accept such offer. The offer shall be
accepted by execution of a Restricted Stock Purchase Agreement in the form
determined by the Administrator.

            (b) Repurchase Option. Unless the Administrator determines
otherwise, the Restricted Stock Purchase Agreement shall grant the Company a
repurchase option exercisable upon the voluntary or involuntary termination of
the purchaser's service with the Company for any reason (including death or
Disability). The purchase price for Shares repurchased pursuant to the
Restricted Stock Purchase Agreement shall be the original price paid by the
purchaser and may be paid by cancellation of any indebtedness of the purchaser
to the Company. The repurchase option shall lapse at a rate determined by the
Administrator.

            (c) Other Provisions. The Restricted Stock Purchase Agreement shall
contain such other terms, provisions and conditions not inconsistent with the
Plan as may be determined by the Administrator in its sole discretion.

            (d) Rights as a Stockholder. Once the Stock Purchase Right is
exercised, the purchaser shall have the rights equivalent to those of a
stockholder, and shall be a stockholder when


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his or her purchase is entered upon the records of the duly authorized transfer
agent of the Company. No adjustment will be made for a dividend or other right
for which the record date is prior to the date the Stock Purchase Right is
exercised, except as provided in Section 13 of the Plan.

      12. Non-Transferability of Options and Stock Purchase Rights. Unless
determined otherwise by the Administrator, an Option or Stock Purchase Right 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. If the
Administrator makes an Option or Stock Purchase Right transferable, such Option
or Stock Purchase Right shall contain such additional terms and conditions as
the Administrator deems appropriate.

      13. Adjustments Upon Changes in Capitalization, Dissolution, Merger or
Asset Sale.

            (a) Changes in Capitalization. Subject to any required action by the
stockholders of the Company, the number of shares of Common Stock covered by
each outstanding Option and Stock Purchase Right, and the number of shares of
Common Stock which have been authorized for issuance under the Plan but as to
which no Options or Stock Purchase Rights have yet been granted or which have
been returned to the Plan upon cancellation or expiration of an Option or Stock
Purchase Right, as well as the price per share of Common Stock covered by each
such outstanding Option or Stock Purchase Right, shall 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 Company; provided, however, that conversion of any
convertible securities of the Company shall not be deemed to have been "effected
without receipt of consideration." Such adjustment shall be made by the Board,
whose determination in that respect shall be final, binding and conclusive.
Except as expressly provided herein, no issuance by the Company of shares of
stock of any class, or securities convertible into shares of stock of any class,
shall affect, and no adjustment by reason thereof shall be made with respect to,
the number or price of shares of Common Stock subject to an Option or Stock
Purchase Right.

            (b) Dissolution or Liquidation. In the event of the proposed
dissolution or liquidation of the Company, the Administrator shall notify each
Optionee as soon as practicable prior to the effective date of such proposed
transaction. The Administrator in its discretion may provide for an Optionee to
have the right to exercise his or her Option until ten (10) days prior to such
transaction as to all of the Optioned Stock covered thereby, including Shares as
to which the Option would not otherwise be exercisable. In addition, the
Administrator may provide that any Company repurchase option applicable to any
Shares purchased upon exercise of an Option or Stock Purchase Right shall lapse
as to all such Shares, provided the proposed dissolution or liquidation takes
place at the time and in the manner contemplated. To the extent it has not been
previously exercised, an Option or Stock Purchase Right will terminate
immediately prior to the consummation of such proposed action.

            (c) Merger or Asset Sale. In the event of a merger of the Company
with or into another corporation, or the sale of substantially all of the assets
of the Company, each outstanding Option and Stock Purchase Right shall be
assumed or an equivalent option or right substituted by the


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successor corporation or a Parent or Subsidiary of the successor corporation. In
the event that the successor corporation refuses to assume or substitute for the
Option or Stock Purchase Right, the Optionee shall fully vest in and have the
right to exercise the Option or Stock Purchase Right as to all of the Optioned
Stock, including Shares as to which it would not otherwise be vested or
exercisable. If an Option or Stock Purchase Right becomes fully vested and
exercisable in lieu of assumption or substitution in the event of a merger or
sale of assets, the Administrator shall notify the Optionee in writing or
electronically that the Option or Stock Purchase Right shall be fully vested and
exercisable for a period of fifteen (15) days from the date of such notice, and
the Option or Stock Purchase Right shall terminate upon the expiration of such
period. For the purposes of this paragraph, the Option or Stock Purchase Right
shall be considered assumed if, following the merger or sale of assets, the
option or right confers the right to purchase or receive, for each Share of
Optioned Stock subject to the Option or Stock Purchase Right immediately prior
to the merger or sale of assets, the consideration (whether stock, cash, or
other securities or property) received in the merger or sale of assets by
holders of Common Stock for each Share held on the effective date of the
transaction (and if holders were offered a choice of consideration, the type of
consideration chosen by the holders of a majority of the outstanding Shares);
provided, however, that if such consideration received in the merger or sale of
assets is not solely common stock of the successor corporation or its Parent,
the Administrator may, with the consent of the successor corporation, provide
for the consideration to be received upon the exercise of the Option or Stock
Purchase Right, for each Share of Optioned Stock subject to the Option or Stock
Purchase Right, to be solely common stock of the successor corporation or its
Parent equal in fair market value to the per share consideration received by
holders of Common Stock in the merger or sale of assets.

      14. Date of Grant. The date of grant of an Option or Stock Purchase Right
shall be, for all purposes, the date on which the Administrator makes the
determination granting such Option or Stock Purchase Right, or such other later
date as is determined by the Administrator. Notice of the determination shall be
provided to each Optionee within a reasonable time after the date of such grant.

      15. Amendment and Termination of the Plan.

            (a) Amendment and Termination. The Board may at any time amend,
alter, suspend or terminate the Plan.

            (b) Stockholder Approval. The Company shall obtain stockholder
approval of any Plan amendment to the extent necessary and desirable to comply
with Applicable Laws.

            (c) Effect of Amendment or Termination. No amendment, alteration,
suspension or termination of the Plan shall impair the rights of any Optionee,
unless mutually agreed otherwise between the Optionee and the Administrator,
which agreement must be in writing and signed by the Optionee and the Company.
Termination of the Plan shall not affect the Administrator's ability to exercise
the powers granted to it hereunder with respect to Options granted under the
Plan prior to the date of such termination.


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      16. Conditions Upon Issuance of Shares.

            (a) Legal Compliance. Shares shall not be issued pursuant to the
exercise of an Option or Stock Purchase Right unless the exercise of such Option
or Stock Purchase Right and the issuance and delivery of such Shares shall
comply with Applicable Laws and shall be further subject to the approval of
counsel for the Company with respect to such compliance.

            (b) Investment Representations. As a condition to the exercise of an
Option or Stock Purchase Right, the Company may require the person exercising
such Option or Stock Purchase Right to represent and warrant at the time of any
such exercise that the Shares are being purchased only for investment and
without any present intention to sell or distribute such Shares if, in the
opinion of counsel for the Company, such a representation is required.

      17. Inability to Obtain Authority. The inability of the Company to obtain
authority from any regulatory body having jurisdiction, which authority is
deemed by the Company's counsel to be necessary to the lawful issuance and sale
of any Shares hereunder, shall relieve the Company of any liability in respect
of the failure to issue or sell such Shares as to which such requisite authority
shall not have been obtained.

      18. Reservation of Shares. The Company, during the term of this Plan, will
at all times reserve and keep available such number of Shares as shall be
sufficient to satisfy the requirements of the Plan.

      19. Stockholder Approval. The Plan shall be subject to approval by the
stockholders of the Company within twelve (12) months after the date the Plan is
adopted. Such stockholder approval shall be obtained in the manner and to the
degree required under Applicable Laws.


                                      -12-
<PAGE>   13

                            KABIRA TECHNOLOGIES, INC.

                                 2000 STOCK PLAN

                             STOCK OPTION AGREEMENT


        Unless otherwise defined herein, the terms defined in the Plan shall
have the same defined meanings in this Option Agreement.

I.      NOTICE OF STOCK OPTION GRANT

        [OPTIONEE'S NAME AND ADDRESS]

        You have been granted an option to purchase Common Stock of the Company,
subject to the terms and conditions of the Plan and this Option Agreement, as
follows:

        Grant Number                        ____________________________________

        Date of Grant                       ____________________________________

        Vesting Commencement Date           ____________________________________

        Exercise Price per Share            $___________________________________

        Total Number of Shares Granted      ____________________________________

        Total Exercise Price                $___________________________________

        Type of Option:                     ___ Incentive Stock Option

                                            ___ Nonstatutory Stock Option

        Term/Expiration Date:               ____________________________________


        Vesting Schedule:

        This Option may be exercised, in whole or in part, in accordance with
the following schedule:

        [25% OF THE SHARES SUBJECT TO THE OPTION SHALL VEST TWELVE MONTHS AFTER
THE VESTING COMMENCEMENT DATE, AND 1/48 OF THE SHARES SUBJECT TO THE OPTION
SHALL VEST EACH MONTH THEREAFTER, SUBJECT TO THE OPTIONEE CONTINUING TO BE A
SERVICE PROVIDER ON SUCH DATES].



<PAGE>   14

        Termination Period:

        This Option may be exercised for [THREE MONTHS] after Optionee ceases to
be a Service Provider. Upon the death or Disability of the Optionee, this Option
may be exercised for [TWELVE MONTHS] after Optionee ceases to be a Service
Provider. In no event shall this Option be exercised later than the
Term/Expiration Date as provided above.

II.     AGREEMENT

        A.     Grant of Option.

               The Plan Administrator of the Company hereby grants to the
Optionee named in the Notice of Grant attached as Part I of this Agreement (the
"Optionee") an option (the "Option") to purchase the number of Shares, as set
forth in the Notice of Grant, at the exercise price per share set forth in the
Notice of Grant (the "Exercise Price"), subject to the terms and conditions of
the Plan, which is incorporated herein by reference. Subject to Section 15(c) of
the Plan, in the event of a conflict between the terms and conditions of the
Plan and the terms and conditions of this Option Agreement, the terms and
conditions of the Plan shall prevail.

               If designated in the Notice of Grant as an Incentive Stock Option
("ISO"), this Option is intended to qualify as an Incentive Stock Option under
Section 422 of the Code. However, if this Option is intended to be an Incentive
Stock Option, to the extent that it exceeds the $100,000 rule of Code Section
422(d) it shall be treated as a Nonstatutory Stock Option ("NSO").

        B.     Exercise of Option.

               (a)     Right to Exercise. This Option is exercisable during its
term in accordance with the Vesting Schedule set out in the Notice of Grant and
the applicable provisions of the Plan and this Option Agreement.

               (b)     Method of Exercise. This Option is exercisable by
delivery of an exercise notice, in the form attached as Exhibit A (the "Exercise
Notice"), which shall state the election to exercise the Option, the number of
Shares in respect of which the Option is being exercised (the "Exercised
Shares"), and such other representations and agreements as may be required by
the Company pursuant to the provisions of the Plan. The Exercise Notice shall be
completed by the Optionee and delivered to [TITLE] of the Company. The Exercise
Notice shall be accompanied by payment of the aggregate Exercise Price as to all
Exercised Shares. This Option shall be deemed to be exercised upon receipt by
the Company of such fully executed Exercise Notice accompanied by such aggregate
Exercise Price.

                       No Shares shall be issued pursuant to the exercise of
this Option unless such issuance and exercise complies with Applicable Laws.
Assuming such compliance, for income tax purposes the Exercised Shares shall be
considered transferred to the Optionee on the date the Option is exercised with
respect to such Exercised Shares.


                                      -2-
<PAGE>   15

        C.     Method of Payment.

               Payment of the aggregate Exercise Price shall be by any of the
following, or a combination thereof, at the election of the Optionee:

               1.____cash; or

               2.____check; or

               3.____consideration received by the Company under a cashless
exercise program implemented by the Company in connection with the Plan; or

               4.____surrender of other Shares which (i) in the case of Shares
acquired upon exercise of an option, have been owned by the Optionee for more
than six (6) months on the date of surrender, and (ii) have a Fair Market Value
on the date of surrender equal to the aggregate Exercise Price of the Exercised
Shares.

        D.     Non-Transferability of Option.

               This Option may not be transferred in any manner otherwise than
by will or by the laws of descent or distribution and may be exercised during
the lifetime of Optionee only by the Optionee. The terms of the Plan and this
Option Agreement shall be binding upon the executors, administrators, heirs,
successors and assigns of the Optionee.

        E.     Term of Option.

               This Option may be exercised only within the term set out in the
Notice of Grant, and may be exercised during such term only in accordance with
the Plan and the terms of this Option Agreement.

        F.     Tax Consequences.

               Some of the federal tax consequences relating to this Option, as
of the date of this Option, are set forth below. THIS SUMMARY IS NECESSARILY
INCOMPLETE, AND THE TAX LAWS AND REGULATIONS ARE SUBJECT TO CHANGE. THE OPTIONEE
SHOULD CONSULT A TAX ADVISER BEFORE EXERCISING THIS OPTION OR DISPOSING OF THE
SHARES.

        G.     Exercising the Option.

               1. Nonstatutory Stock Option. The Optionee may incur regular
federal income tax liability upon exercise of a NSO. The Optionee will be
treated as having received compensation income (taxable at ordinary income tax
rates) equal to the excess, if any, of the Fair Market Value of the Exercised
Shares on the date of exercise over their aggregate Exercise Price. If the
Optionee is an Employee or a former Employee, the Company will be required to
withhold from his or her compensation or collect from Optionee and pay to the
applicable taxing authorities an amount in cash equal to a percentage of this
compensation income at the time of exercise, and may refuse to


                                      -3-
<PAGE>   16


honor the exercise and refuse to deliver Shares if such withholding amounts are
not delivered at the time of exercise.

                2.____Incentive Stock Option. If this Option qualifies as an
ISO, the Optionee will have no regular federal income tax liability upon its
exercise, although the excess, if any, of the Fair Market Value of the Exercised
Shares on the date of exercise over their aggregate Exercise Price will be
treated as an adjustment to alternative minimum taxable income for federal tax
purposes and may subject the Optionee to alternative minimum tax in the year of
exercise. In the event that the Optionee ceases to be an Employee but remains a
Service Provider, any Incentive Stock Option of the Optionee that remains
unexercised shall cease to qualify as an Incentive Stock Option and will be
treated for tax purposes as a Nonstatutory Stock Option on the date three (3)
months and one (1) day following such change of status.

                3.____Disposition of Shares.

                      (a) NSO. If the Optionee holds NSO Shares for at least one
year, any gain realized on disposition of the Shares will be treated as
long-term capital gain for federal income tax purposes.

                      (b) ISO. If the Optionee holds ISO Shares for at least one
year after exercise and two years after the grant date, any gain realized on
disposition of the Shares will be treated as long-term capital gain for federal
income tax purposes. If the Optionee disposes of ISO Shares within one year
after exercise or two years after the grant date, any gain realized on such
disposition will be treated as compensation income (taxable at ordinary income
rates) to the extent of the excess, if any, of the lesser of (A) the difference
between the Fair Market Value of the Shares acquired on the date of exercise and
the aggregate Exercise Price, or (B) the difference between the sale price of
such Shares and the aggregate Exercise Price. Any additional gain will be taxed
as capital gain, short-term or long-term depending on the period that the ISO
Shares were held.

                      (c) Notice of Disqualifying Disposition of ISO Shares. If
the Optionee sells or otherwise disposes of any of the Shares acquired pursuant
to an ISO on or before the later of (i) two years after the grant date, or (ii)
one year after the exercise date, the Optionee shall immediately notify the
Company in writing of such disposition. The Optionee agrees that he or she may
be subject to income tax withholding by the Company on the compensation income
recognized from such early disposition of ISO Shares by payment in cash or out
of the current earnings paid to the Optionee.

        H.     Entire Agreement; Governing Law.

               The Plan is incorporated herein by reference. The Plan and this
Option Agreement constitute the entire agreement of the parties with respect to
the subject matter hereof and supersede in their entirety all prior undertakings
and agreements of the Company and Optionee with respect to the subject matter
hereof, and may not be modified adversely to the Optionee's interest except by
means of a writing signed by the Company and Optionee. This agreement is
governed by the internal substantive laws, but not the choice of law rules, of
California.

                                      -4-

<PAGE>   17

        I.     NO GUARANTEE OF CONTINUED SERVICE.

               OPTIONEE ACKNOWLEDGES AND AGREES THAT THE VESTING OF SHARES
PURSUANT TO THE VESTING SCHEDULE HEREOF IS EARNED ONLY BY CONTINUING AS A
SERVICE PROVIDER AT THE WILL OF THE COMPANY (AND NOT THROUGH THE ACT OF BEING
HIRED, BEING GRANTED AN OPTION OR PURCHASING SHARES HEREUNDER). OPTIONEE FURTHER
ACKNOWLEDGES AND AGREES THAT THIS AGREEMENT, THE TRANSACTIONS CONTEMPLATED
HEREUNDER AND THE VESTING SCHEDULE SET FORTH HEREIN DO NOT CONSTITUTE AN EXPRESS
OR IMPLIED PROMISE OF CONTINUED ENGAGEMENT AS A SERVICE PROVIDER FOR THE VESTING
PERIOD, FOR ANY PERIOD, OR AT ALL, AND SHALL NOT INTERFERE WITH OPTIONEE'S RIGHT
OR THE COMPANY'S RIGHT TO TERMINATE OPTIONEE'S RELATIONSHIP AS A SERVICE
PROVIDER AT ANY TIME, WITH OR WITHOUT CAUSE.

        By your signature and the signature of the Company's representative
below, you and the Company agree that this Option is granted under and governed
by the terms and conditions of the Plan and this Option Agreement. Optionee has
reviewed the Plan and this Option Agreement in their entirety, has had an
opportunity to obtain the advice of counsel prior to executing this Option
Agreement and fully understands all provisions of the Plan and Option Agreement.
Optionee hereby agrees to accept as binding, conclusive and final all decisions
or interpretations of the Administrator upon any questions relating to the Plan
and Option Agreement. Optionee further agrees to notify the Company upon any
change in the residence address indicated below.


OPTIONEE:                                 KABIRA TECHNOLOGIES, INC.


-------------------------------           -------------------------------------
Signature                                 By


-------------------------------           -------------------------------------
Print Name                                Title

-------------------------------
Residence Address


-------------------------------

                                      -5-

<PAGE>   18


                                    EXHIBIT A

                            KABIRA TECHNOLOGIES, INC.

                                 2000 STOCK PLAN

                                 EXERCISE NOTICE



Kabira Technologies, Inc.
One McInnis Parkway
San Rafael, CA 94903

Attention:  [Title]


        1. Exercise of Option. Effective as of today, ________________, _____,
the undersigned ("Purchaser") hereby elects to purchase ______________ shares
(the "Shares") of the Common Stock of Kabira Technologies, Inc. (the "Company")
under and pursuant to the 2000 Stock Plan (the "Plan") and the Stock Option
Agreement dated, _____ (the "Option Agreement"). The purchase price for the
Shares shall be $_____, as required by the Option Agreement.

        2. Delivery of Payment. Purchaser herewith delivers to the Company the
full purchase price for the Shares.

        3. Representations of Purchaser. Purchaser acknowledges that Purchaser
has received, read and understood the Plan and the Option Agreement and agrees
to abide by and be bound by their terms and conditions.

        4. Rights as Shareholder. Until the issuance (as evidenced by the
appropriate entry on the books of the Company or of a duly authorized transfer
agent of the Company) of the Shares, no right to vote or receive dividends or
any other rights as a shareholder shall exist with respect to the Optioned
Stock, notwithstanding the exercise of the Option. The Shares so acquired shall
be issued to the Optionee as soon as practicable after exercise of the Option.
No adjustment will be made for a dividend or other right for which the record
date is prior to the date of issuance, except as provided in Section 13 of the
Plan.

        5. Tax Consultation. Purchaser understands that Purchaser may suffer
adverse tax consequences as a result of Purchaser's purchase or disposition of
the Shares. Purchaser represents that Purchaser has consulted with any tax
consultants Purchaser deems advisable in connection with the purchase or
disposition of the Shares and that Purchaser is not relying on the Company for
any tax advice.


<PAGE>   19

        6. Entire Agreement; Governing Law. The Plan and Option Agreement are
incorporated herein by reference. This Agreement, the Plan and the Option
Agreement constitute the entire agreement of the parties with respect to the
subject matter hereof and supersede in their entirety all prior undertakings and
agreements of the Company and Purchaser with respect to the subject matter
hereof, and may not be modified adversely to the Purchaser's interest except by
means of a writing signed by the Company and Purchaser. This Agreement is
governed by the internal substantive laws, but not the choice of law rules, of
California.

Submitted by:                             Accepted by:

PURCHASER:                                KABIRA TECHNOLOGIES, INC.


-------------------------------           -------------------------------------
Signature                                 By

-------------------------------           -------------------------------------
Print Name            Its

Address:                                  Address:

                                          One McInnis Parkway
-------------------------------           San Rafael, CA 94903


-------------------------------

                                          --------------------------------------
                                          Date Received


                                      -2-