<PAGE>

                                                                    EXHIBIT 10.1

                                REPLICASE, INC.

                            1998 STOCK OPTION PLAN

     1.   Purposes of the Plan.  This 1998 Stock Option Plan is designed to
          --------------------
attract and retain the best available personnel for positions of substantial
responsibility 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 of an Option
and subject to the applicable provisions of Section 422 of the Code and the
regulations promulgated thereunder.

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

          (a)  "Administrator" means the Board or any of its Committees
appointed pursuant to Section 4 of the Plan.

          (b)  "Applicable Laws" means the legal requirements relating to the
administration of stock option plans under U.S. state corporate laws, U.S.
federal and state securities laws, the Code and the applicable laws of any
foreign country or jurisdiction where Options 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 appointed by the Board of Directors
in accordance with Section 4 of the Plan.

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

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

          (h)  "Consultant" means any person who is engaged by the Company or
any Parent or Subsidiary to render consulting or advisory services and is
compensated for such services, and any Director of the Company whether
compensated for such services or not. If the Company registers any class of any
equity security pursuant to the Exchange Act, the term Consultant shall
thereafter not include Directors who are not compensated for their services or
are paid only a Director's fee by the Company.

          (i)  "Continuous Status as an Employee or Consultant" means that the
employment or consulting relationship with the Company, any Parent or Subsidiary
is not interrupted or terminated.  Continuous Status as an Employee or
Consultant shall not be considered interrupted 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.  A
leave of absence approved by the Company shall include sick leave, military
leave, or any other personal leave approved by an authorized representative of
the
<PAGE>

Company.  For purposes of Incentive Stock Options, no such leave may exceed 90
days, unless reemployment upon expiration of such leave is guaranteed by statute
or contract, including Company policies.  If reemployment upon expiration of a
leave of absence approved by the Company is not so guaranteed, on the 91st 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.

          (j)  "Director" means a member of the Board of Directors of the
Company.

          (k)  "Employee" means any person, including Officers and Directors,
employed by the Company or any Parent or Subsidiary of the Company.  The payment
of a Director's fee by the Company shall not 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, its Fair Market
     Value 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; or

               (iii) In the absence of an established market for the Common
     Stock, the Fair Market Value thereof 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.

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

          (p)  "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.

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

          (r)  "Optioned Stock" means the Common Stock subject to an Option.

          (s)  "Optionee" means an Employee or Consultant who receives an
Option.

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

          (u)  "Plan" means this 1998 Stock Option Plan.

          (v)  "Section 16(b)" means Section 16(b) of the Securities Exchange
Act of 1934, as amended.

          (w)  "Share" means a share of the Common Stock, as adjusted in
accordance with Section 12 below.

          (x)   "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 12 of
          -------------------------
the Plan, the maximum aggregate number of Shares that may be subject to option
and sold under the Plan is Two Million Nine Hundred Twenty-Nine Thousand Four
Hundred Thirty-Four (2,929,434) 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 pursuant to an option exchange program, the
unpurchased Shares that were subject thereto shall become available for future
grant or sale under the Plan (unless the Plan has terminated).  However, Shares
that have actually been issued under the Plan, upon exercise of an Option, shall
not be returned to the Plan and shall not become available for future
distribution under the Plan, except that if Shares are repurchased by the
Company at their original purchase price, and the original purchaser of such
Shares did not receive any benefits of ownership of such Shares, such Shares
shall become available for future grant under the Plan.  For purposes of the
preceding sentence, voting rights shall not be considered a benefit of Share
ownership.

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

          (a)  Initial Plan Procedure.  Prior to the date, if any, upon which
               ----------------------
the Company becomes subject to the Exchange Act, the Plan shall be administered
by the Board or a Committee appointed by the Board.

          (b)  Plan Procedure after the Date, if any, upon which the Company
               -------------------------------------------------------------
Becomes Subject to the Exchange Act.
-----------------------------------

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

               (ii)  Administration with Respect to Directors and Officers. With
                     -----------------------------------------------------
     respect to grants of Options to Employees who are also Officers or
     Directors of the Company, the Plan shall be administered by (A) the Board
     if the Board may administer the Plan in compliance with the rules under
     Rule 16b-3 promulgated under the Exchange Act or any successor thereto
     ("Rule 16b-3") relating to the disinterested administration of employee
     benefit plans under which Section 16(b) exempt discretionary grants and
     awards of equity securities are to be made, or (B) a Committee designated
     by the Board to administer the Plan, which Committee shall be constituted
     to comply with the rules under Rule l6b-3 relating to the disinterested
     administration of employee benefit plans under which Section 16(b) exempt
     discretionary grants and awards of equity securities are to be made. Once
     appointed, such Committee shall 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 and appoint additional members
     thereof, remove members (with or without cause) and appoint new members in
     substitution therefor, fill vacancies, however caused, and remove all
     members of the Committee and thereafter directly administer the Plan, all
     to the extent permitted by the rules under Rule l6b-3 relating to the
     disinterested administration of employee benefit plans under which Section
     16(b) exempt discretionary grants and awards of equity securities are to be
     made.

               (iii) Administration with Respect to Other Employees and
                     --------------------------------------------------
     Consultants.  With respect to grants of Options and to Employees or
     -----------
     Consultants who are neither Directors nor Officers of the Company, the Plan
     shall be administered by (A) the Board or (B) a Committee designated by the
     Board, which committee shall be constituted in such a manner as to satisfy
     Applicable Laws.  Once appointed, such Committee shall 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 and appoint
     additional members thereof, remove members (with or without cause) and
     appoint new members in substitution therefor, fill vacancies, however
     caused, and remove all members of the Committee and thereafter directly
     administer the Plan, all to the extent permitted by the Applicable Laws.

          (c)  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 such Committee, and subject to the approval of any relevant authorities,
including the approval, if required, of any stock exchange upon which the Common
Stock is listed, the Administrator shall have the authority in its discretion:

               (i)   to determine the Fair Market Value of the Common Stock, in
     accordance with Section 2(m) of the Plan;

                                       4
<PAGE>

               (ii)   to select the Consultants and Employees to whom Options
     may from time to time be granted hereunder;

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

               (iv)   to determine the number of Shares to be covered by each
     such award granted hereunder;

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

               (vi)   to determine the terms and conditions of any award granted
     hereunder;

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

               (viii) 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 such Option has declined since the date the Option was granted;

               (ix)   to provide for the early exercise of Options for the
     purchase of unvested shares subject to such terms and conditions as the
     Administrator may determine; and

               (x)    to construe and interpret the terms of the Plan and awards
     granted pursuant to the Plan.

          (d)  Effect of Administrator's Decision.  All decisions,
               ----------------------------------
determinations and interpretations of the Administrator shall be final and
binding on all Optionees and any other holders of any Options.

     5.   Elipibility.
          -----------

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

          (b)  Each Option shall be designated in the written 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 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 5(b), Incentive Stock Options shall be taken into account in the order
in which they were granted. The

                                       5
<PAGE>

Fair Market Value of the Shares shall be determined as of the time the Option
with respect to such Shares is granted.

          (c)  Neither the Plan nor any Option shall confer upon any Optionee
any right with respect to continuation of his or her employment or consulting
relationship with the Company, nor shall it interfere in any way with his or her
right or the Company's right to terminate his or her employment or consulting
relationship at any time, with or without cause.

          (d)  Upon the Company or a successor corporation issuing any class of
common equity securities required to be registered under Section 12 of the
Exchange Act or upon the Plan being 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 shall apply to grants of Options to
Employees:

               (i)  The foregoing limitations shall be adjusted proportionately
     in connection with any change in the Company's capitalization as described
     in Section 11.

               (ii) 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 11), the cancelled Option shall be counted
     against the limit set forth in subsection (i) above.  For this purpose, if
     the exercise price of an Option is reduced, such reduction will be treated
     as a cancellation of the Option and the grant of a new Option.

     6.   Term of Plan.  The Plan shall become effective upon the earlier to
          ------------
occur of its adoption by the Board of Directors or its approval by the
stockholders of the Company, as described in Section 17 of the Plan.  It shall
continue in effect for a term of ten (10) years unless sooner terminated under
Section 13 of the Plan.

     7.   Term of Option.  The term of each Option shall be the term stated in
          --------------
the Option Agreement; provided, however, that the term shall be no more than ten
(10) years from the date of grant thereof.  In the case of an Incentive Stock
Option granted to an Optionee who, at the time the 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 term of the Option shall
be five (5) years from the date of grant thereof or such shorter term as may be
provided in the Option Agreement.

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

          (a)  The per share exercise price for the Shares to be issued upon
exercise of an Option shall be such price as is determined by the Administrator,
but shall be subject to the following:

               (i)  In the case of an Incentive Stock Option

                    (A)  granted to an Employee who, at the time of grant of
     such Option, owns stock representing more than ten percent (10%) of the
     voting power

                                       6
<PAGE>

     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 other Employee, 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

                    (A)  granted to a person who, at the time of grant of such
     Option, 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 the grant.

                    (B)  granted to any other person, the per Share exercise
     price shall be no less than 85% of the Fair Market Value per Share on the
     date of grant.

          (b)  The consideration to be paid for the Shares to be issued upon
exercise of an Option, including the method of payment, shall be determined by
the Administrator (and, in the case of an Incentive Stock Option, shall be
determined at the time of grant).  Such consideration may consist of (1) cash,
(2) check, (3) promissory note, (4) other Shares that (x) 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 (y) have a Fair Market Value on
the date of surrender equal to the aggregate exercise price of the Shares as to
which such Option shall be exercised, (5) delivery of a properly executed
exercise notice together with such other documentation as the Administrator and
a broker, if applicable, shall require to effect an exercise of the Option and
delivery to the Company 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 as to the type of consideration to accept, the
Administrator shall consider if acceptance of such consideration may be
reasonably expected to benefit the Company.

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

          (a)  Procedure for Exercise; Rights as a Stockholder.  Any Option
               -----------------------------------------------
granted hereunder shall be exercisable at such times and under such conditions
as determined by the Administrator, including performance criteria with respect
to the Company and/or the Optionee, and as shall be permissible under the terms
of the Plan.

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

          An Option shall be deemed to be exercised when written notice of such
exercise has been given to the Company in accordance with the terms of the
Option by the person entitled to exercise the Option and full payment for the
Shares with respect to which the Option is exercised has been received by the
Company.  Full payment may, as authorized by the

                                       7
<PAGE>

Administrator, consist of any consideration and method of payment allowable
under Section 8(b) hereof.  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 stock certificate evidencing such Shares, no right to vote,
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 stock certificate promptly upon
exercise of the Option.  No adjustment shall be made for a dividend or other
right for which the record date is prior to the date the stock certificate is
issued, except as provided in Section 11 hereof.

          Exercise of an Option in any manner shall result in a decrease in the
number of Shares that thereafter may be 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 Employment or Consulting Relationship.  In the
               ----------------------------------------------------
event of termination of an Optionee's Continuous Status as an Employee or
Consultant (but not in the event of an Optionee's change of status from Employee
to Consultant (in which case an Employee's Incentive Stock Option shall
automatically convert to a Nonstatutory Stock Option on the date three (3)
months and one day following such change of status) or from Consultant to
Employee), such Optionee may, but only within such period of time as is
determined by the Administrator, of at least thirty (30) days, with such
determination in the case of an Incentive Stock Option not exceeding three (3)
months after the date of such termination (but in no event later than the
expiration date of the term of such Option as set forth in the Option
Agreement), exercise his or her Option to the extent that the Optionee was
entitled to exercise it at the date of such termination.  To the extent that the
Optionee was not entitled to exercise the Option at the date of such
termination, or if the Optionee does not exercise such Option to the extent so
entitled within the time specified herein, the Option shall terminate.

          (c)  Disability of Optionee.  In the event of termination of an
               ----------------------
Optionee's Continuous Status as an Employee or Consultant as a result of his or
her disability, the Optionee may, but only within twelve (12) months from the
date of such termination (and in no event later than the expiration date of the
term of such Option as set forth in the Option Agreement), exercise the Option
to the extent otherwise entitled to exercise it at the date of such termination.
If such disability is not a "disability" as such term is defined in Section
22(e)(3) of the Code, in the case of an Incentive Stock Option such Incentive
Stock Option shall automatically cease to be treated as an Incentive Stock
Option and shall be treated for tax purposes as a Nonstatutory Stock Option on
the day three months and one day following such termination.  To the extent that
the Optionee was not entitled to exercise the Option at the date of termination,
or if the Optionee does not exercise such Option to the extent so entitled
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.  In the event of the death of an Optionee, the
               -----------------
Option may be exercised at any time within twelve (12) months following the date
of death (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
acquired the right to exercise the Option by bequest

                                       8
<PAGE>

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 his or her entire Option, the Shares
covered by the unexercisable portion of the Option shall immediately revert to
the Plan.  If, after the Optionee's death, the Optionee's estate or a person who
acquires the right to exercise the Option by bequest or inheritance does not
exercise the Option within the time specified herein, the Option shall
terminate, and the Shares covered by such Option shall revert to the Plan.

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

          (f)  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.

     10.  Non-Transferability of Options.  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 Upon Changes in Capitalization or Merge.
          ---------------------------------------------------

          (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 the number of shares of Common Stock that have been
authorized for issuance under the Plan but as to which no Option has yet been
granted or that has 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 such
outstanding Option, 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.
The 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.

          (b)  Dissolution or Liquidation.  In the event of the proposed
               --------------------------
dissolution or liquidation of the Company, the Administrator shall notify the
Optionee at least fifteen (15) days prior to such proposed action.  To the
extent it has not been previously

                                       9
<PAGE>

exercised, the Option shall terminate immediately prior to the consummation of
such proposed action.

          (c)  Merge.  In the event of a merger of the Company with or into
               -----
another corporation, each outstanding Option may be assumed or an equivalent
option or right may be substituted by such successor corporation or a parent or
subsidiary of such successor corporation.  If, in such event, an Option is not
assumed or substituted, the Option shall terminate as of the date of the closing
of the merger.  For the purposes of this paragraph, the Option shall be
considered assumed if, following the merger, the Option confers the right to
purchase or receive, for each Share of Optioned Stock subject to the Option
immediately prior to the merger, the consideration (whether stock, cash, or
other securities or property) received in the merger by holders of Common Stock
for each Share held on the effective date of the transaction (and if the holders
are offered a choice of consideration, the type of consideration chosen by the
holders of a majority of the outstanding Shares).  If such consideration
received in the merger 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, for each Share of Optioned Stock subject to the Option, 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.

     12.  Time of Granting Options.  The date of grant of an Option shall, for
          ------------------------
all purposes, be the date on which the Administrator makes the determination
granting such Option, or such other date as is determined by the Administrator.
Notice of the determination shall be given to each Employee or Consultant to
whom an Option is so granted within a reasonable time after the date of such
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 no amendment, alteration, suspension
or discontinuation shall be made that would impair the rights of any Optionee
under any grant theretofore made, without his or her consent.  In addition, to
the extent necessary and 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
Company shall obtain stockholder approval of any Plan amendment in such a manner
and to such a degree as required.

          (b)  Effect of Amendment or Termination.  Any such amendment or
               ----------------------------------
termination of the Plan shall not affect Options already granted, and such
Options shall remain in full force and effect as if this Plan had not been
amended or terminated, unless mutually agreed otherwise between the Optionee and
the Administrator, which agreement must be in writing and signed by the Optionee
and the Company.

     14.  Conditions upon Issuance of Shares.  Shares shall not be issued
          ----------------------------------
pursuant to the exercise of an Option unless the exercise of such Option and the
issuance and delivery of such Shares pursuant thereto shall comply with all
relevant provisions of law, including, without

                                       10
<PAGE>

limitation, the Securities Act of 1933, as amended, the Exchange Act, the rules
and regulations promulgated thereunder, and the requirements of any stock
exchange upon which the Shares may then be listed, and shall be further subject
to the approval of counsel for the Company with respect to such compliance.

          As a condition to the exercise of an Option, the Company may require
the person exercising such Option 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 by any of
the aforementioned relevant provisions of law.

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

          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.

     16.  Agreements.  Options shall be evidenced by written agreements in such
          ----------
form as the Administrator shall approve from time to time.

     17.  Stockholder Approval.  Continuance of the Plan shall be subject to
          --------------------
approval by the stockholders of the Company within twelve (12) months before or
after the date the Plan is adopted.  Such stockholder approval shall be obtained
in the degree and manner required under Applicable Laws and the rules of any
stock exchange upon which the Common Stock is listed.

     18.  Information to Optionees and Purchasers.  The Company shall provide to
          ---------------------------------------
each Optionee and to each individual who acquires Shares pursuant to the Plan,
not less frequently than annually during the period such Optionee or purchaser
has one or more Options outstanding, and, in the case of an individual who
acquires Shares pursuant to the Plan, during the period such individual owns
such Shares, copies of annual financial statements.  The Company shall not be
required to provide such statements to key employees whose duties in connection
with the Company assure their access to equivalent information.

                                       11
<PAGE>

                                REPLICASE, INC.

                            1998 STOCK OPTION PLAN

                            STOCK OPTION AGREEMENT


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

I.   NOTICE OF STOCK OPTION GRANT
     ----------------------------

     ((F1))

     You have been granted an option to purchase Common Stock of the Company,
subject to the terms and conditions of the Plan and this Stock Option Agreement.
The Terms of your grant are set forth below:

     Date of Grant                          ((F2))

     Vesting Commencement Date              ((F3))

     Exercise Price per Share               $0. 10 per share

     Total Number of Shares Granted         ((F4))

     Total Exercise Price                   $((F5))

     Type of Option:                X       Incentive Stock Option
                                  ------

                                  ------    Nonstatutory Stock Option

     Term/Expiration Date:                  ((F61))

     Exercise and Vesting Schedule:
     -----------------------------

     The Shares subject to this Option shall vest according to the following
schedule:

     No Shares are currently vested 25% of the Shares subject to the Option
(rounded down to the next whole number of shares) shall vest one year after the
Vesting Commencement Date, and 1/48th of the Shares subject to the Option
(rounded down to the next whole number of shares) shall vest on the first day of
each month thereafter, so that all of the Shares shall be vested on the first
day of the 48th month after the Vesting Commencement Date.
<PAGE>

Termination Period:
-------------------

     This Option may be exercised, to the extent vested, for thirty days after
termination of Optionee's employment or consulting relationship.  A longer
period may be applicable, however, upon death or disability of Optionee as
provided in the Plan, but in no event later than the Term/Expiration Date as
provided above.

II.  AGREEMENT
     ---------

     1.   Grant of Option.  The Company hereby grants to the Optionee an Option
          ---------------
to purchase the Common Stock (the "Shares") set forth in the Notice of Grant, at
the exercise price per share set forth in the Notice of Grant (the "Exercise
Price").  Notwithstanding anything to the contrary anywhere else in this Option
Agreement, this grant of an Option is subject to the terms, definitions and
provisions of the 1998 Stock Option Plan (the "Plan") adopted by the Company,
which is incorporated herein by reference.

          If designated in the Notice of Grant as an Incentive Stock Option
("ISO"), this Option is intended to qualify as an ISO as defined in Section 422
of the Code.

     2.   Exercise of Option.  This Option is exercisable as follows:
          ------------------

          (i)  Right to Exercise.
               -----------------

               (a)  Subject to subsections 2(i)(b) through 2(i)(d) below, this
Option shall be exercisable cumulatively according to the vesting schedule set
out in the Notice of Grant. Shares subject to this Option shall vest based on
continued employment of or consulting services by Optionee with the Company.

               (b)  This Option may not be exercised for a fraction of a Share.

               (c)  In the event of Optionee's death, disability or other
termination of the employment or consulting relationship, the exercisability of
the Option is governed by Sections 7, 8 and 9 below.

               (d)  In no event may this Option be exercised after the date of
expiration of the term of this Option as set forth in the Notice of Grant.

          (ii) Method of Exercise.  This Option shall be exercisable by written
               ------------------
Notice (in the form attached as Exhibit A).  The Notice must state the number of
                                ---------
Shares for which the Option is being exercised, and such other representations
and agreements with respect to such shares of Common Stock as may be required by
the Company pursuant to the provisions of the Plan.  The Notice must be signed
by the Optionee and shall be delivered in person or by certified mail to the
Secretary of the Company.  The Notice must be accompanied by payment of the
Exercise Price.  This Option shall be deemed to be exercised upon receipt by the
Company of such written Notice accompanied by the Exercise Price.
<PAGE>

          No Shares shall be issued pursuant to the exercise of an Option unless
such issuance and such exercise comply with all relevant provisions of law and
the requirements of any stock exchange upon which the Shares may then be listed.
Assuming such compliance, for income tax purposes the Shares shall be considered
transferred to the Optionee on the date on which the Option is exercised with
respect to such Shares.

     3.   Optionee's Representations.  If the Shares purchasable pursuant to the
          --------------------------
exercise of this Option have not been registered under the Securities Act of
1933, as amended (the "Securities Act"), at the time this Option is exercised,
Optionee shall, if required by the Company, concurrently with the exercise of
all or any portion of this Option, deliver to the Company his or her Investment
Representation Statement in the form attached hereto as Exhibit B.
                                                        ---------

     4.   Lock-Up Period.  Optionee hereby agrees that if so requested by the
          --------------
Company or any representative of the underwriters (the "Managing Underwriter")
in connection with any registration of the offering of any securities of the
Company under the Securities Act, Optionee shall not sell or otherwise transfer
any Shares or other securities of the Company during the 180-day period (or such
longer period as may be requested in writing by the Managing Underwriter and
agreed to in writing by the Company) (the "Market Standoff Period") following
the effective date of a registration statement of the Company filed under the
Securities Act; provided, however, that such restriction shall apply only to the
first registration statement of the Company to become effective under the
Securities Act that includes securities to be sold on behalf of the Company to
the public in an underwritten public offering under the Securities Act.  The
Company may impose stop-transfer instructions with respect to securities subject
to the foregoing restrictions until the end of such Market Standoff Period.

     5.   Method of Payment.  Payment of the Exercise Price shall be by any of
          -----------------
the following, or a combination thereof, at the election of the Optionee:

          (i)    cash; or

          (ii)   check; or

          (iii)  surrender of other shares of Common Stock of the Company which
(A) in the case of Shares acquired pursuant to the exercise of a Company option,
have been owned by the Optionee for more than six (6) months on the date of
surrender, and (B) have a Fair Market Value on the date of surrender equal to
the Exercise Price of the Shares as to which the Option is being exercised; or

          (iv)   to the extent permitted by the Administrator, delivery of a
properly executed exercise notice together with such other documentation as the
Administrator and the broker, if applicable, shall require to effect an exercise
of the Option and delivery to the Company of the sale or loan proceeds required
to pay the Exercise Price.

     6.   Restrictions on Exercise.  This Option may not be exercised until the
          ------------------------
Plan has been approved by the stockholders of the Company.  If the issuance of
Shares upon such exercise
<PAGE>

or if the method of payment for such shares would constitute a violation of any
applicable federal or state securities or other law or regulation, then the
Option may also not be exercised.  The Company may require Optionee to make any
representation and warranty to the Company as may be required by any applicable
law or regulation before allowing the Option to be exercised.

     7.   Termination of Relationship.  If an Optionee's Continuous Status as an
          ---------------------------
Employee or Consultant terminates, Optionee may exercise this Option during the
Termination Period set out in the Notice of Grant, to the extent the Option was
vested at the date of such termination (the "Termination Date").  To the extent
that Optionee was not vested in this Option at the date of such termination, or
if Optionee does not exercise this Option within the time specified herein, the
Option shall terminate.

     8.   Disability of Optionee.  Despite Section 6 above, if an Optionee's
          ----------------------
Continuous Status as an Employee or Consultant terminates as a result of his or
her disability, Optionee may exercise the Option to the extent the Option was
vested at the date of such termination, but only within twelve (12) months from
the date of such termination (and in no event later than the expiration date of
the term of such Option as set forth in the Stock Option Agreement).  To the
extent that Optionee is not vested in the Option at the date of termination, or
if Optionee does not exercise such Option within the time specified herein, the
Option shall terminate, and the Shares covered by such Option shall revert to
the Plan.

     9.   Death of Optionee.  If Optionee's Continuous Status as an Employee or
          -----------------
Consultant terminates as a result of the death of Optionee, the vested portion
of the Option may be exercised at any time within twelve (12) months following
the date of death (but in no event later than the date of expiration of the term
of this Option as set forth in Section 10 below) by Optionee's estate or by a
person who acquires the right to exercise the Option by bequest or inheritance.
To the extent that Optionee is not vested in the Option at the date of death, or
if the Option is not exercised within the time specified herein, the Option
shall terminate, and the Shares covered by such Option shall revert to the Plan.

     10.  Non-Transferability of Option.  This Option may not be transferred in
          -----------------------------
any manner except by will or by the laws of descent or distribution.  It may be
exercised during the lifetime of Optionee only by Optionee.  The terms of this
Option shall be binding upon the executors, administrators, heirs, successors
and assigns of the Optionee.

     11.  Term of Option.  This Option may be exercised only within the term set
          --------------
out in the Notice of Grant.

     12.  Tax Consequences.  Set forth below is a brief summary as of the date
          ----------------
of this Option of some of the federal and state tax consequences of exercise of
this Option and disposition of the Shares.  THIS SUMMARY IS NECESSARILY
INCOMPLETE, AND THE TAX LAWS AND REGULATIONS ARE SUBJECT TO CHANGE.  OPTIONEE
SHOULD CONSULT A TAX ADVISER BEFORE EXERCISING THIS OPTION OR DISPOSING OF THE
SHARES.
<PAGE>

          (i)    Exercise of ISO. If this Option qualifies as an ISO, there will
                 ---------------
be no regular federal income tax liability or state income tax liability upon
the exercise of the Option, although the excess, if any, of the Fair Market
Value of the Shares on the date of exercise over the Exercise Price will be
treated as an adjustment to the alternative minimum tax for federal tax purposes
and may subject the Optionee to the alternative minimum tax in the year of
exercise.

          (ii)   Exercise of ISO Following Disability.  If the Optionee's
                 ------------------------------------
Continuous Status as an Employee or Consultant terminates as a result of
disability that is not total and permanent disability as defined in Section
22(e)(3) of the Code, to the extent permitted on the date of termination, the
Optionee must exercise an ISO within 90 days of such termination for the ISO to
be qualified as an ISO.

          (iii)  Exercise of NSO.  There may be a regular federal income tax
                 ---------------
liability and state income tax liability upon the exercise of an 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 Shares on the date of exercise over the Exercise Price.  If Optionee is
an Employee, the Company will be required to withhold from Optionee's
compensation or collect from Optionee and pay to the applicable taxing
authorities an amount equal to a percentage of this compensation income at the
time of exercise.  If the Optionee is subject to Section 16 of the Securities
Act of 1934, as amended, the date of income recognition may be deferred for up
to six months.

          (iv)   Disposition of Shares. In the case of an NSO, if Shares are
                 ---------------------
held for the minimum long-term capital gain holding period in effect at the time
of disposition, any gain realized on disposition of the Shares will be treated
as long-term capital gain for federal and state income tax purposes. In the case
of an ISO, if Shares transferred pursuant to the Option are held for the minimum
long-term capital gain holding period in effect at the time of disposition (and
provided such holding period comprises at least one year after exercise of the
Option) and are disposed of at least two years after the Date of Grant, any gain
realized on disposition of the Shares will also be treated as long-term capital
gain for federal and state income tax purposes. If Shares purchased under an ISO
are disposed of after such one-year period following exercise, but before the
expiration of the minimum long-term capital gain holding period in effect at the
time of disposition, then gain realized on such disposition may be taxed as a
short-term capital gain, which may or may not be equivalent to taxation as
compensation income (taxable at ordinary income rates). If Shares purchased
under an ISO are disposed of within such one-year period or within two years
after the Date of Grant, any gain realized on such disposition will be treated
as compensation income to the extent of the difference between the Exercise
Price and the lesser of (1) the Fair Market Value of the Shares on the date of
exercise, or (2) the sale price of the Shares.

          (v)    Notice of Disqualifying Disposition of ISO Shares. If the
                 -------------------------------------------------
Option granted to Optionee herein is an ISO, and if Optionee sells or otherwise
disposes of any of the Shares acquired pursuant to the ISO on or before the
later of (1) the date two years after the Date of Grant, or (2) the date one
year after the date of exercise, the Optionee shall immediately notify the
Company in writing of such disposition. Optionee agrees that Optionee may be
subject to
<PAGE>

income tax withholding by the Company on the compensation income recognized by
the Optionee.

                                   REPLICASE, INC.



                                   By:____________________________

                                   Title:_________________________
<PAGE>

     OPTIONEE ACKNOWLEDGES AND AGREES THAT THE VESTING OF SHARES PURSUANT TO THE
OPTION HEREOF IS EARNED ONLY BY CONTINUING CONSULTANCY OR EMPLOYMENT AT THE WILL
OF THE COMPANY (NOT THROUGH THE ACT OF BEING HIRED, BEING GRANTED THIS OPTION OR
ACQUIRING SHARES HEREUNDER). OPTIONEE FURTHER ACKNOWLEDGES AND AGREES THAT
NOTHING IN THIS AGREEMENT, NOR IN THE COMPANY'S 1998 STOCK OPTION PLAN WHICH IS
INCORPORATED HEREIN BY REFERENCE, SHALL CONFER UPON OPTIONEE ANY RIGHT WITH
RESPECT TO CONTINUATION OF EMPLOYMENT OR CONSULTANCY BY THE COMPANY, NOR SHALL
IT INTERFERE IN ANY WAY WITH OPTIONEE'S RIGHT OR THE COMPANY'S RIGHT TO
TERMINATE OPTIONEE'S EMPLOYMENT OR CONSULTANCY AT ANY TIME, WITH OR WITHOUT
CAUSE.

     Optionee acknowledges receipt of a copy of the Plan and represents that he
is familiar with the terms and provisions thereof.  Optionee hereby accepts this
Option subject to all of the terms and provisions hereof.  Optionee has reviewed
the Plan and this Option in their entirety, has had an opportunity to obtain the
advice of counsel prior to executing this Option and fully understands all
provisions of the Option.  Optionee hereby agrees to accept as binding,
conclusive and final all decisions or interpretations of the Administrator upon
any questions arising under the Plan or this Option.  Optionee further agrees to
notify the Company upon any change in the residence address indicated below.

Dated: _____________________       _________________________________
                                   ((F1))

                                   Residence Address:

                                   __________________________________

                                   __________________________________
<PAGE>

                                   EXHIBIT A

                            1998 STOCK OPTION PLAN

                                EXERCISE NOTICE

Replicase, Inc.
Attn: President
1816 Embarcadero Road
Palo Alto, CA 94303

     1.   Exercise of Option.  Effective as of today, ____________, 19_, the
          ------------------
undersigned ("Optionee") hereby elects to exercise Optionee's option to purchase
______________ shares of the Common Stock (the "Shares") of Replicase, Inc., a
Delaware corporation (the "Company"), under and pursuant to the 1998 Stock
Option Plan (the "Plan") and the [ ] Incentive [ ] Nonstatutory Stock Option
Agreement dated _____________, 19__ (the "Option Agreement").

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

     3.   Rights as Stockholder. Until the stock certificate evidencing such
          ---------------------
Shares is 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 stock certificate 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 stock certificate
is issued, except as provided in Section 11 of the Plan.

     Optionee shall enjoy rights as a stockholder until such time as Optionee
disposes of the Shares or the Company and/or its assignee(s) exercises the Right
of First Refusal hereunder.  Upon such exercise, Optionee shall have no further
rights as a holder of the Shares so purchased except the right to receive
payment for the Shares so purchased in accordance with the provisions of this
Agreement, and Optionee shall forthwith cause the certificate(s) evidencing the
Shares so purchased to be surrendered to the Company for transfer or
cancellation.

     4.   Company's Right of First Refusal. Before any Shares held by Optionee
          --------------------------------
or any transferee (either being sometimes referred to herein as the "Holder")
may be sold or otherwise transferred (including transfer by gift or operation of
law), the Company or its assignee(s) shall have a right of first refusal to
purchase the Shares on the terms and conditions set forth in this Section (the
"Right of First Refusal").

          (a)  Notice of Proposed Transfer. The Holder of the Shares shall
               ---------------------------
deliver to the Company a written notice (the "Notice") stating: (i) the Holder's
bona fide intention to sell or
<PAGE>

otherwise transfer such Shares; (ii) the name of each proposed purchaser or
other transferee ("Proposed Transferee"); (iii) the number of Shares to be
transferred to each Proposed Transferee; and (iv) the bona fide cash price or
other consideration for which the Holder proposes to transfer the Shares (the
"Offered Price"), and the Holder shall offer the Shares at the Offered Price to
the Company or its assignee(s).

          (b)  Exercise of Right of First Refusal. Within thirty (30) days after
               ----------------------------------
receipt of the Notice, the Company and/or its assignee(s) may elect in writing
to purchase all, but not less than all, of the Shares proposed to be transferred
to any one or more of the Proposed Transferees. The purchase price will be
determined in accordance with subsection (c) below.

          (c)  Purchase Price. The purchase price ("Purchase Price") for the
               --------------
Shares repurchased under this Section shall be the Offered Price. If the Offered
Price includes consideration other than cash, the cash equivalent value of the
non-cash consideration shall be determined by the Board of Directors of the
Company in good faith.

          (d)  Payment. Payment of the Purchase Price shall be made, at the
               -------
option of the Company or its assignee(s), in cash (by check), by cancellation of
all or a portion of any outstanding indebtedness of the Holder to the Company
(or, in the case of repurchase by an assignee, to the assignee), or by any
combination thereof within 30 days after receipt of the Notice or in the manner
and at the times set forth in the Notice.

          (e)  Holder's Right to Transfer. If all of the Shares proposed in the
               --------------------------
Notice to be transferred to a given Proposed Transferee are not purchased by the
Company and/or its assignee(s) as provided in this Section, then the Holder may
sell or otherwise transfer such Shares to that Proposed Transferee at the
Offered Price or at a higher price, provided that such sale or other transfer is
consummated within 120 days after the date of the Notice and provided further
that any such sale or other transfer is effected in accordance with any
applicable securities laws and the Proposed Transferee agrees in writing that
the provisions of this Section shall continue to apply to the Shares in the
hands of such Proposed Transferee. If the Shares described in the Notice are not
transferred to the Proposed Transferee within such period, a new Notice shall be
given to the Company, and the Company and/or its assignees shall again be
offered the Right of First Refusal as provided herein before any Shares held by
the Holder may be sold or otherwise transferred.

          (f)  Exception for Certain Family Transfers. Anything to the contrary
               --------------------------------------
contained in this Section notwithstanding, the transfer of any or all of the
Shares during the Optionee's lifetime or on the Optionee's death by will or
intestacy to the Optionee's immediate family or a trust for the benefit of the
Optionee's immediate family shall be exempt from the provisions of this Section.
"Immediate Family" as used herein shall mean spouse, lineal descendant or
antecedent, father, mother, brother or sister or stepchild (whether or not
adopted). In such case, the transferee or other recipient shall receive and hold
the Shares so transferred subject to the provisions of this Section, and there
shall be no further transfer of such Shares except in accordance with the terms
of this Section.
<PAGE>

          (g)  Termination of Right of First Refusal. The Right of First Refusal
               -------------------------------------
shall terminate as to any Shares 90 days after the first sale of Common Stock of
the Company to the general public pursuant to a registration statement filed
with and declared effective by the Securities and Exchange Commission under the
Securities Act of 1933, as amended.

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

     6.   Restrictive Legends and Stop-Transfer Orders.
          --------------------------------------------

          (a)  Legends. Optionee understands and agrees that the Company shall
               -------
cause the legends set forth below or legends substantially equivalent thereto,
to be placed upon any certificate(s) evidencing ownership of the Shares together
with any other legends that may be required by state or federal securities laws:

          THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED
          UNDER THE SECURITIES ACT OF 1933 (THE "ACT") AND MAY NOT BE
          OFFERED, SOLD OR OTHERWISE TRANSFERRED, PLEDGED OR
          HYPOTHECATED UNLESS AND UNTIL REGISTERED UNDER THE ACT OR,
          IN THE OPINION OF COUNSEL IN FORM AND SUBSTANCE SATISFACTORY
          TO THE ISSUER OF THESE SECURITIES, SUCH OFFER, SALE OR
          TRANSFER, PLEDGE OR HYPOTHECATION IS IN COMPLIANCE
          THEREWITH.

          THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO
          CERTAIN RESTRICTIONS ON TRANSFER AND RIGHT OF FIRST REFUSAL
          OPTIONS HELD BY THE ISSUER OR ITS ASSIGNEE(S) AS SET FORTH
          IN THE EXERCISE NOTICE BETWEEN THE ISSUER AND THE ORIGINAL
          HOLDER OF THESE SHARES, A COPY OF WHICH MAY BE OBTAINED AT
          THE PRINCIPAL OFFICE OF THE ISSUER. SUCH TRANSFER
          RESTRICTIONS AND RIGHT OF FIRST REFUSAL ARE BINDING ON
          TRANSFEREES OF THESE SHARES.

          (b)  Stop-Transfer Notices.  Optionee agrees that, in order to ensure
               ---------------------
compliance with the restrictions referred to herein, the Company may issue
appropriate "stop transfer" instructions to its transfer agent, if any, and
that, if the Company transfers its own securities, it may make appropriate
notations to the same effect in its own records.
<PAGE>

          (c)  Refusal to Transfer.  The Company shall not be required (i) to
               -------------------
transfer on its books any Shares that have been sold or otherwise transferred in
violation of any of the provisions of this Agreement or (ii) to treat as owner
of such Shares or to accord the right to vote or pay dividends to any purchaser
or other transferee to whom such Shares shall have been so transferred.

     7.   Successors and Assigns. The Company may assign any of its rights under
          ----------------------
this Agreement to single or multiple assignees, and this Agreement shall inure
to the benefit of the successors and assigns of the Company. Subject to the
restrictions on transfer herein set forth, this Agreement shall be binding upon
Optionee and his or her heirs, executors, administrators, successors and
assigns.

     8.   Intermetation. Any dispute regarding the interpretation of this
          -------------
Agreement shall be submitted by Optionee or by the Company forthwith to the
Company's Board of Directors or the committee thereof that administers the Plan,
which shall review such dispute at its next regular meeting. The resolution of
such a dispute by the Board or committee shall be final and binding on the
Company and on Optionee.

     9.   Governing Law; Severability.  This Agreement shall be governed by and
          ---------------------------
construed in accordance with the laws of the State of California excluding that
body of law pertaining to conflicts of law.  Should any provision of this
Agreement be determined by a court of law to be illegal or unenforceable, the
other provisions shall nevertheless remain effective and shall remain
enforceable.

     10.  Notices.  Any notice required or permitted hereunder shall be given in
          -------
writing and shall be deemed effectively given upon personal delivery or upon
deposit in the United States mail by certified mail, with postage and fees
prepaid, addressed to the other party at its address as shown below beneath its
signature, or to such other address as such party may designate in writing from
time to time to the other party.

     11.  Further Instruments. The parties agree to execute such further
          -------------------
instruments and to take such further action as may be reasonably necessary to
carry out the purposes and intent of this Agreement.

     12.  Delivery of Payment. Optionee herewith delivers to the Company the
          -------------------
full Exercise Price for the Shares.

     13.  Entire Agreement.  The Plan and Notice of Grant/Option Agreement are
          ----------------
incorporated herein by reference.  This Agreement, the Plan, the Option
Agreement and the Investment Representation Statement constitute the entire
agreement of the parties and supersede
<PAGE>

in their entirety all prior undertakings and agreements of the Company and
Optionee with respect to the subject matter hereof.

Submitted by:                           Accepted by:

OPTIONEE:                               REPLICASE, INC.


_______________________________         By:____________________________

                                        Its:___________________________


Address:
-------


_______________________________

_______________________________

_______________________________
<PAGE>

                                   EXHIBIT B
                                   ---------

                      INVESTMENT REPRESENTATION STATEMENT

OPTIONEE  :

COMPANY   :    REPLICASE, INC.

SECURITY  :    COMMON STOCK

AMOUNT    :

DATE      :

In connection with the purchase of the above-listed Securities, the undersigned
Optionee represents to the Company the following:

          (a)  Optionee is aware of the Company's business affairs and financial
condition and has acquired sufficient information about the Company to reach an
informed and knowledgeable decision to acquire the Securities.  Optionee is
acquiring these Securities for investment for Optionee's own account only and
not with a view to, or for resale in connection with, any "distribution" thereof
within the meaning of the Securities Act of 1933, as amended (the "Securities
Act").

          (b)  Optionee acknowledges and understands that the Securities
constitute "restricted securities" under the Securities Act and have not been
registered under the Securities Act in reliance upon a specific exemption
therefrom, which exemption depends upon, among other things, the bona fide
nature of Optionee's investment intent as expressed herein. In this connection,
Optionee understands that, in the view of the Securities and Exchange
Commission, the statutory basis for such exemption may be unavailable if
Optionee's representation was predicated solely upon a present intention to hold
these Securities for the minimum capital gains period specified under tax
statutes, for a deferred sale, for or until an increase or decrease in the
market price of the Securities, or for a period of one year or any other fixed
period in the future. Optionee further understands that the Securities must be
held indefinitely unless they are subsequently registered under the Securities
Act or an exemption from such registration is available. Optionee further
acknowledges and understands that the Company is under no obligation to register
the Securities. Optionee understands that the certificate evidencing the
Securities will be imprinted with a legend which prohibits the transfer of the
Securities unless they are registered or such registration is not required in
the opinion of counsel satisfactory to the Company and any other legend required
under applicable state securities laws.

          (c)  Optionee is familiar with the provisions of Rule 701 and Rule
144, each promulgated under the Securities Act, which, in substance, permit
limited public resale of "restricted securities" acquired, directly or
indirectly from the issuer thereof, in a non-public offering subject to the
satisfaction of certain conditions. Rule 701 provides that if the issuer
<PAGE>

qualifies under Rule 701 at the time of the grant of the Option to the Optionee,
the exercise will be exempt from registration under the Securities Act.  In the
event the Company becomes subject to the reporting requirements of Section 13 or
15(d) of the Securities Exchange Act of 1934, ninety (90) days thereafter (or
such longer period as any market stand-off agreement may require) the Securities
exempt under Rule 701 may be resold, subject to the satisfaction of certain of
the conditions specified by Rule 144, including: (1) the resale being made
through a broker in an unsolicited "broker's transaction" or in transactions
directly with a market maker (as said term is defined under the Securities
Exchange Act of 1934); and, in the case of an affiliate, (2) the availability of
certain public information about the Company, (3) the amount of Securities being
sold during any three month period not exceeding the limitations specified in
Rule 144(e), and (4) the timely filing of a Form 144, if applicable.

     In the event that the Company does not qualify under Rule 701 at the time
of grant of the Option, then the Securities may be resold in certain limited
circumstances subject to the provisions of Rule 144, which requires the resale
to occur not less than one year after the later of the date the Securities were
sold by the Company or the date the Securities were sold by an affiliate of the
Company, within the meaning of Rule 144; and, in the case of acquisition of the
Securities by an affiliate, or by a non-affiliate who subsequently holds the
Securities less than two years, the satisfaction of the conditions set forth in
sections (1), (2), (3) and (4) of the paragraph immediately above.

          (d)  Optionee further understands that in the event all of the
applicable requirements of Rule 701 or 144 are not satisfied, registration under
the Securities Act, compliance with Regulation A, or some other registration
exemption will be required; and that, notwithstanding the fact that Rules 144
and 701 are not exclusive, the Staff of the Securities and Exchange Commission
has expressed its opinion that persons proposing to sell private placement
securities other than in a registered offering and otherwise than pursuant to
Rules 144 or 701 will have a substantial burden of proof in establishing that an
exemption from registration is available for such offers or sales, and that such
persons and their respective brokers who participate in such transactions do so
at their own risk. Optionee understands that no assurances can be given that any
such other registration exemption will be available in such event.

                                   Signature of Optionee:



                                   ______________________________________

Dated: __________________, 19__