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                                                                    EXHIBIT 10.2


                    1996 ISOCOR DIRECTORS' STOCK OPTION PLAN

                              AMENDED AND RESTATED

                               AS OF MAY 13, 1999

     1. Purposes of the Plan. The purposes of this Directors' Stock Option Plan
are to attract and retain the best available personnel for service as Directors
of the Company, to provide additional incentive to the Outside Directors of the
Company to serve as Directors, and to encourage their continued service on the
Board.

     All options granted hereunder shall be "nonstatutory" stock options".

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

          (a) "Board" shall mean the Board of Directors of the Company.

          (b) "Code" shall mean the Internal Revenue Code of 1986, as amended.

          (c) "Common Stock" shall mean the Common Stock of the Company.

          (d) "Company" shall mean ISOCOR, a California corporation.

          (e) "Continuous Status as a Director" shall mean the absence of any
interruption or termination of service as a Director.

          (f) "Director" shall mean a member of the Board.

          (g) "Employee" shall mean 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 in and of
itself to constitute "employment" by the Company.

          (h) "Exchange Act" shall mean the Security Exchange Act of 1934, as
amended.

          (i) "Option" shall mean a stock option granted pursuant to the Plan.

          (j) "Optioned Stock" shall mean the Common Stock subject to an Option.

          (k) "Optionee" shall mean an Outside Director who receives an Option.

          (l) "Outside Director" shall mean a Director who is not an Employee.

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


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          (n) "Plan" shall mean this 1996 Directors' Stock Option Plan.

          (o) "Share" shall mean a share of the Common Stock, as adjusted in
accordance with Section 11 of the Plan.

          (p) "Subsidiary" shall mean 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 11 of
the Plan, the maximum aggregate number of Shares which may be optioned and sold
under the Plan is 150,000 Shares (the "Pool") of Common Stock. The Shares may be
authorized, but unissued, or reacquired Common Stock.

     If an Option should expire or become unexercisable for any reason without
having been exercised in full, the unpurchased Shares which were subject thereto
shall, unless the Plan shall have been terminated, become available for future
grant under the Plan- If Shares which were acquired upon exercise of an Option
are subsequently repurchased by the Company, such Shares shall not in any event
be returned to the Plan and shall not become available for future grant under
the Plan.

     4. Administration of and Grants of Options under the Plan.

          (a) Administrator. Except as otherwise required herein, the Plan shall
be administered by the Board.

          (b) Procedure for Grants. All grants of Options hereunder shall be
automatic and nondiscretionary and shall be made strictly in accordance with the
following provisions:

               (i) No person shall have any discretion to select which Outside
Directors shall be granted Options or to determine the number of Shares to be
covered by Options granted to Outside Directors.

               (ii) Each Outside Director who has not, prior to the Company's
initial offering of Common Stock to the public, received an option grant
pursuant to the Company's 1992 Stock. Option Plan, shall be automatically
granted an Option to purchase 25,000 Shares (the "First Option") on the date on
which the later of the following events occurs: (A) January 18, 1996, or (B) the
date on which such person first becomes an Outside Director, whether through
election by the shareholders of the Company or appointment by the Board of
Directors to fill a vacancy.

               (iii) Each Outside Director who has, prior to the Company's
initial offering of Common Stock to the public, received an option grant
pursuant to the Company's 1992 Stock Option Plan, shall be automatically granted
an Option to purchase 5,000 Shares (the "Modified First Option") on the date on
which the later of the following events occurs: (A) January 18, 1996, or (B) the
date on which such person first becomes an Outside Director, whether through
election by the shareholders of the Company or appointment by the Board of
Directors to fill a vacancy,

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               (iv) After the First Option has been granted to an Outside
Director, such Outside Director (including Directors who have received a
Modified First Option) shall thereafter be automatically granted an Option to
purchase 6,250 Shares (a "Subsequent Option") on the first calendar day of the
Company's fiscal year, provided that, on such date, he or she shall have served
on the Board for at least six (6) months.

               (v) Notwithstanding the provisions of subsections (ii) and (iii)
hereof, in the event that a grant would cause the number of Shares subject to
outstanding Options plus the number of Shares previously purchased upon exercise
of Options to exceed the Pool, then each such automatic grant shall be for that
number of Shares determined by dividing the total number of Shares remaining
available for grant by the number of Outside Directors on the automatic grant
date. Any further grants shall then be deferred until such time, if any, as
additional Shares become available for grant under the Plan through action of
the shareholders to increase the number of Shares which may be issued under the
Plan or through cancellation or expiration of Options previously granted
hereunder.

               (vi) Notwithstanding the provisions of subsections (ii) and (iii)
hereof any grant of an Option made before the Company has obtained shareholder
approval of the Plan in accordance with Section 17 hereof shall be conditioned
upon obtaining such shareholder approval of the Plan in accordance with Section
17 hereof.

               (vii) The terms of each First Option granted hereunder shall be
as follows:

                    (1) the First Option shall be exercisable only while the
Outside Director remains a Director of the Company, except as set forth in
Section 9 hereof.

                    (2) the exercise price per Share shall be 100% of the fair
market value per Share at le beginning of the date of grant of the First Option,
determined in accordance with Section 8 hereof


                    (3) the First Option shall become exercisable in
installments cumulatively as to 25% of the Shares subject to the First Option on
each of the first, second, third and fourth anniversaries of the date of grant
of the First Option.

               (viii) The terms of each Modified First Option granted hereunder
shall be as follows;

                    (1) the Modified First Option on shall be exercisable only
while the Outside Director remains a Director of the Company, except as set
forth in Section 9 hereof.

                    (2) the exercise price per Share shall be 100% of the fair
market value per Share at the beginning of the date of grant of the First
Option, determined in accordance with Section 8 hereof.

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                    (3) the Modified First Option shall become exercisable in
installments cumulatively as to 50% of the Shares subject to the Modified First
Option on each of the third and fourth anniversaries of the due of grant of the
Modified First Option.

               (ix) The terms of each Subsequent Option granted hereunder shall
be as follows:

                    (1) the Subsequent Option shall be exercisable only while
the Outside Director remains a Director of the Company, except as set forth in
Section 9 hereof.

                    (2) the exercise price per Share shall be 100% of the fair
market value per Share at the beginning of the date of grant of the Subsequent
Option, determined in accordance with Section 8 hereof.

                    (3) the Subsequent Option shall become exercisable as to one
hundred percent (100%) of the Shares subject to the Subsequent Option on the
fourth anniversary of the date of grant of the Subsequent Option.

          (c) Powers of the Board. Subject to the provisions and restrictions of
the Plan, the Board shall have the authority, in its discretion: (i) to
determine, upon review of relevant information and in accordance with Section
8(b) of the Plan, the fair market value of the Common Stock; (ii) to determine
the exercise price per share of Options to be granted, which exercise price
shall be determined in accordance with Section 8(a) of the Plan; (iii) to
interpret the Plan; (iv) to prescribe, amend and rescind rules and regulations
relating to the Plan; (v) to authorize any person to execute on behalf of the
Company any instrument required to effectuate the grant of an Option previously
granted here-under; and (vi) to make: all other determinations deemed necessary
or advisable for the administration of the Plan.

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

          (e) Suspension or Termination of Option. If the President or his or
her designee reasonably believes that an Optionee has committed an act of
misconduct, the President may suspend the Optionee's right to exercise any
option pending a determination by the Board of Directors (excluding the Outside
Director accused of such misconduct). If the Board of Directors (excluding the
Outside Director accused of such misconduct) determines an Optionee has
committed an act of embezzlement, fraud, dishonesty, nonpayment of an obligation
owed to the Company, breach of fiduciary duty or deliberate disregard of the
Company rules resulting in loss, damage or injury to the Company, or if an
Optionee makes an unauthorized disclosure of any Company trade secret or
confidential information, engages in any conduct constituting unfair
competition, induces any Company customer to breach a contract with the Company
or induces any principal for whom the Company acts as agent to terminate such
agency relationship, neither the Optionee nor his or her estate shall be
entitled to exercise any option whatsoever. In making such determination, the
Board

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of Directors (excluding the Outside Director accused of such misconduct) shall
act fairly and shall give the Optionee an opportunity to appear and present
evidence on Optionee's behalf at a hearing before the Board or a committee of
the Board.

     5. Eligibility. Options may be granted only to Outside Directors. All
Options shall be automatically granted in accordance with the terms set forth in
Section 4(b) hereof. An Outside Director who has been granted an Option may, if
he or she is otherwise eligible, be granted an additional Option or Options in
accordance with such provisions.

     The Plan shall not confer upon any Optionee any right with respect to
continuation of service as a Director or nomination to serve as a Director, nor
shall it interfere in any way with any rights which the Director or the Company
may have to terminate his or her directorship at any time.

     6. Term of Plan; Effective Date. The Plan shall become effective on the
date of its adoption by the Board of Directors of the Company. 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 ten (10) years from the
date of grant thereof.

     8. 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 100% of the fair market value
per Share on the date of grant of the Option.

          (b) Fair Market Value. The fair market value shall be determined by
the Board in its discretion; provided, however, that where there is a public
market for the Common Stock, the fair market value per Share shall be the mean
of the bid and asked prices of the Common Stock in the over-the-counter market
on the date of grant, as reported in The Wall Street Journal (or, if not so
reported, as otherwise reported by the National Association of Securities
Dealers Automated Quotation ("NASDAQ" System) or, in the event the Common Stock
is traded on the NASDAQ National Market or listed on a stock exchange, the fair
market value per Share shall be the closing price on such system or exchange on
the date of grant of the Option, as reported in The Wall Street Journal. With
respect to any Options granted hereunder concurrently with the initial
effectiveness of the Plan, the fair market value shall be equal to the initial
public offering price of the Company's Common Stock as set forth on the cover
page of the prospectus relating to such initial public offering.

          (c) Form of Consideration. The consideration to be paid for the Shares
to be issued upon exercise of an Option shall consist entirely of cash, check,
other Shares of Common Stock having 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 (which, if acquired from the Company, shall have been held
for at least six months), or any combination of such methods of payment and/or
any other consideration or method of payment as shall be permitted under
applicable corporate law.

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     9. Exercise of Option.

          (a) Procedure for Exercise, Rights as a Shareholder. Any Option
granted hereunder shall be exercisable at such times as are set forth in Section
4(b) hereof, provided, however, that no Options shall be exercisable prior to
shareholder approved of the Plan in accordance with Section 17 hereof has been
obtained.

     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 consist of any consideration and method of payment
allowable under Section 8(c) of the Plan. 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 or receive dividends or any other rights as a shareholder shall
exist with respect to the Optioned Stock, notwithstanding the exercise of the
Option. A share certificate for the number of Shares so acquired shall be issued
to the Optionee as soon as practicable after exercise of the Option. No
adjustment will be made for a dividend or other right for which the record date
is prior to the date the stock certificate is issued, except as provided in
Section 11 of the Plan.

     Exercise of an Option in any manner shall result in a decrease in the
number of Shares which 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 Status as a Director. If an Outside Director ceases
to serve as a Director, he or she may, but only within ninety (90) days (or such
other period of time not exceeding six (6) months as is determined by the Board)
after the date he or she ceases to be a Director of the Company, exercise his or
her Option to the extent that he or she was entitled to exercise it at the date
of such termination. Notwithstanding the foregoing, in no event may the Option
be exercised after its term set forth in Section 7 has expired. To the extent
that such Outside Director was not entitled to exercise an Option at the date of
such termination, or does not exercise such Option (which he or she was entitled
to exercise) within the time specified herein, the Option shall terminate.

          (c) Disability of Optionee. Notwithstanding Section 9(b) above, in the
event a Director is unable to continue his or her service as a Director with the
Company as a result of his or her total and permanent disability (as defined in
Section 22(e)(3) of the Internal Revenue Code), he or she may, but only within
six (6) months (or such other period of time not exceeding twelve (12) months as
is determined by the Board) from the date of such termination, exercise his or
her Option to the extent he or she was entitled to exercise it at the date of
such termination. Notwithstanding the foregoing, in no event may the Option be
exercised after its term set forth in Section 7 has expired. To the extent that
he or she was not entitled to exercise the Option at the date of termination, or
if he

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or she does not exercise such Option (which he or she was entitled to exercise)
within the time specified herein, the Option shall terminate.

          (d) Death of Optionee. In the event of the death of an Optionee:

               (i) During the term of the Option who is, at the time of his or
her death, a Director of the Company and who shall have been in Continuous
Status as a Director since the date of grant of the Option, the Option may be
exercised, at any time within six (6) months (or such lesser period of time as
is determined by the Board) following the date of death, by the Optionee's
estate or by a person who acquired the right to exercise the Option by bequest
or inheritance, but only to the extent of the right to exercise that would have
accrued had the Optionee continued living and remained in Continuous Status as
Director for six (6) months (or such lesser period of time as is determined by
the Board) after the date of death. Notwithstanding the foregoing, in no event
may the Option be exercised after its term set forth in Section 7 has expired.

               (ii) Within three (3) months (or such lesser period of time as is
determined by the Board) after the termination of Continuous Status as a
Director, the Option may be exercised, at any time within six (6) months
following the date of death, by the Optionee's estate or by a person who
acquired the right to exercise the Option by bequest or inheritance, but only to
the extent of the right to exercise that had accrued at the date of termination.
Notwithstanding the foregoing, in no event may the option be exercised after its
term set forth in Section t has expired.

     10. Nontransferability of Options. The Option 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. The designation of a beneficiary
by an Optionee does not constitute a transfer. An Option may be exercised during
the lifetime of an Optionee only by the Optionee or a transferee permitted by
this Section.

     11. Adjustments Upon Changes in Capitalization or Corporate Transactions.

          (a) Adjustment. Subject to any required action by the shareholders of
the Company, the number of shares of Common Stock covered by each outstanding
Option, and the number of shares of Common Stock which have been authorized for
issuance under the Plan but as to which no Options have yet been granted or
which have been returned to the Plan upon cancellation or expiration of an
Option, as well as the price per share of Common Stock covered by each 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;
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

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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) Change of Ownership. In die event of (i) a dissolution or
liquidation of the Company, (ii) a sale of all or substantially all of the
Company's assets, (iii) a merger or consolidation in which the Company is not
the surviving corporation, or (iv) any other capital reorganization in which
more than fifty percent (50%) of the shares of the Company entitled to vote are
exchanged, the Company shall give to the Outside Director, at the time of
adoption of the plan for liquidation, dissolution, sale, merger, consolidation
or reorganization, either a reasonable time thereafter within which to exercise
the Option, prior to the effectiveness of such liquidation, dissolution, sale,
merger, consolidation or reorganization, at the end of which time the Option
shall terminate, or the right to exercise the Option (or receive a substitute
option with comparable terms) as to an equivalent number of shares of stock of
the corporation succeeding the Company or acquiring its business by reason of
such liquidation, dissolution, sale, merger, consolidation or reorganization.

     12. Time of Granting Options. The date of grant of an Option shall, for all
purposes, be the date determined in accordance with Section 4(b) hereof. Notice
of the determination shall be given to each Outside Director 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 amend or terminate the
Plan from time to time in such respects as the Board may deem advisable;
provided that, to the extent necessary and desirable to comply with Rule 16b-3
under the Exchange Act (or any other applicable law or regulation), the Company
shall obtain approval of the shareholders of the Company to Plan amendments to
the extent and in the manner required by such law or regulation. Notwithstanding
the foregoing, the provisions set forth in Section 4 of this Plan (and any other
Sections of this Plan that affect the formula award terms required to be
specified in this Plan by Rule 16b-3) shall not be amended more than once every
six months, other than to comport with changes in the Code, the Employee
Retirement Income Security Act of 1974, as amended, or the rules thereunder.

          (b) Effect of Amendment or Termination. Any such amendment or
termination of the Plan that would impair the rights of any Optionee shall not
affect Options already granted to such Optionee 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 Board, which agreement
must be in writing and signed by the Optionee and the Company.

     14. Conditions Upon Issuance of Shares.

          (a) Compliance. 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 limitation, the Securities Act of 1933, as amended, the
Exchange Act, the rules and regulations promulgated thereunder, state

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securities laws, 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.

          (b) Condition to Exercise. As a condition to the exercise of an
Option, the Company may require the person exercising such Option to represent
and wan-ant 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.

          (c) No Liability. 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.

     15. 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.

     16. Option Agreement. Options shall be evidenced by written option
agreements in such form as the Board shall approve.

     17. Shareholder Approval. Continuance of the Plan shall- be subject to
approval by le shareholders of the Company at or prior to the first annual
meeting of shareholders held subsequent to the granting of an Option hereunder.
If such shareholder approval is obtained at a duly held shareholders' meeting,
it may be obtained by the affirmative vote of the holders of a majority of the
outstanding shares of the Company present or represented and entitled to vote
thereon. Options may be granted, but not exercised, before such shareholder
approval, If the shareholders fail to approve Us Plan within the required time
period, any Options granted under this Plan shall be void, and no additional
options shall be granted.

     18. Additional Restrictions of Rule 16b-3. The terms and conditions of
Options granted hereunder shall comply with the applicable provisions of Rule
16b-3. This Plan and the Options granted hereunder shall be deemed to contain
such additional conditions and restrictions as may be required for this Plan to
qualify as a "formula plan" under Rule 16b-3, as then applicable to the Company,
and to qualify for the maximum exemptions from Section 16 of the Exchange Act
with respect to Plan transactions.

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