<PAGE>

                                                                    Exhibit 10.4

                          ALTIGEN COMMUNICATIONS, INC.

                                 1999 STOCK PLAN

                (AS AMENDED ON JUNE 2, 1999 AND AUGUST 15, 2002)

         1. Purposes of the Plan. The purposes of this 1999 Stock Plan are:

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

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

              o 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 AltiGen Communications, 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.

<PAGE>

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

              (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.

                                       -2-

<PAGE>
              (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.

              (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 Amended and Restated 1999 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-

<PAGE>

         3. Stock Subject to the Plan. Subject to the provisions of Section 13
of the Plan, the maximum aggregate number of Shares which may be optioned and
sold under the Plan is 2,096,247 Shares (post one-for-1.66965 stock split), plus
an annual increase to be added on the first day of the Company's fiscal year
(beginning in 2000) equal to the lesser of (i) 1,796,783 Shares (post
one-for-1.66965 stock split), or (ii) five percent (5%) of the outstanding
Shares on such date, or (iii) such lesser amount as determined by the Board of
Directors. The Shares may be authorized, but unissued, or reacquired Common
Stock.

         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. The Plan may be administered
by different Committees with respect to different groups of Service Providers.

                (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;

                                      -4-

<PAGE>

                (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 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.

                                       -5-

<PAGE>

              (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 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; provided, however, that the term shall be no more than ten
(10) years from the date of grant thereof.

                                      -6-

<PAGE>

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

                    (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

                    (A) granted to a Service Provider who, at the time the
Nonstatutory 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) 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.

                    (C) Granted to any other Service Provider, the per Share
exercise price shall be no less than 85% 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 which must be satisfied before the
Option may be exercised.

                                       -7-

<PAGE>

              (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

                (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. Except in the cases of Options granted to
Officers, Directors and Consultants, Options shall become exercisable at a rate
of no less than 20% per year over five (5) years from the date the Options are
granted. 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

                                       -8-

<PAGE>

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 thirty (30)
days of termination, or such longer period of time as 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 six (6) months of termination, or such longer period of
time as may be 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
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 six (6) months following Optionee's
death, or such longer period of time as may be specified in the Option
Agreement, to the extent that the Option is vested on 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 designated beneficiary, provided such
beneficiary has been designated prior to Optionee's death in a form acceptable
to the Administrator. If no such beneficiary has been designated by the
Optionee, then such Option may be exercised by the personal representative of
the Optionee's estate or by the person(s) to whom the Option is transferred
pursuant to the Optionee's will or in accordance with the laws of descent and
distribution. 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. 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.

                                       -9-

<PAGE>

              (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 terms of the offer
shall comply in all respects with Section 260.140.42 of Title 10 of the
California Code of Regulations. 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, but in no case at a rate of less than 20% per year over five
years from the date of purchase.

              (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 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. Limited Transferability of Options and Stock Purchase Rights.
Unless determined otherwise by the Administrator, Options and Stock Purchase
Rights may not be sold, pledged, assigned, hypothecated, transferred, or
disposed of in any manner other than by will or the laws of descent and
distribution, and may be exercised during the lifetime of the Optionee, only by
the Optionee. If the Administrator in its sole discretion makes an Option
transferable, such Option or Stock Purchase Right may only be transferred (i) by
will, (ii) by the laws of descent and distribution, or (iii) as permitted by
Rule 701 of the Securities Act of 1933, as amended.

                                      -10-

<PAGE>

         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 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

                                      -11-

<PAGE>

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.

         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.

                                      -12-

<PAGE>

         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.

         20. Information to Optionees. 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 participant 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.

                                      -13-