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                                                                    EXHIBIT 10.1

                                     ISOCOR

                             1992 STOCK OPTION PLAN
                            AS AMENDED OCTOBER, 1996

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

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

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

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

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

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

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

                  (f) "Company" means ISOCOR, a California corporation.

                  (g) "Consultant" means any person, including an advisor, who
is engaged by the Company or any Parent or Subsidiary to render consulting
services and is compensated for such services, and any director of the Company
whether compensated for such services or not, provided that if and in the event
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.

                  (h) "Continuous Status as an Employee" means the absence of
any interruption or termination of the employment relationship by the Company or
any Subsidiary. Continuous Status as an Employee shall not be considered
interrupted in the case of: (i) sick leave; (ii) military leave; (iii) any other
leave of absence approved by the Board, provided that such leave is for a period
of not more than ninety (90) days, unless reemployment upon the expiration of
such leave is guaranteed by contract or statute, or unless provided otherwise
pursuant to Company policy adopted from time to time; or (iv) in the case of
transfers between locations of the Company or between the Company, its
Subsidiaries or its successor.




                                     
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                  (i) "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.

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

                  (k) "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
National Market of the National Association of Securities Dealers, Inc.
Automated Quotation ("Nasdaq") System, 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 system or exchange, or the exchange with the
greatest volume of trading in Common Stock) 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 quoted on the Nasdaq
System (but not on the National Market thereof) or 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 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; 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.

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

                  (m) "Named Executive" means (any individual who, on the last
day of the Company's fiscal year, is the chief executive officer of the Company
(or is acting in such capacity) or among the four highest compensated officers
of the Company (other than the chief executive officer). Such officer status
shall be determined pursuant to the executive compensation disclosure rules
under the Exchange Act.

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

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

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

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



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

                  (s) "Plan" means this 1992 Stock Option Plan.

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

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

         3. Stock Subject to the Plan. Subject to the provisions of Section 13
of the Plan, the maximum aggregate number of shares that may be optioned and
sold under the Plan is 2,300,000 shares 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 that were
subject thereto shall, unless the Plan shall have been terminated, become
available for future grant under the Plan.

         4. Administration of the Plan.

                  (a) Composition of Administrator.

                           (i) Multiple Administrative Bodies. If permitted by
Rule 16b-3, and by the legal requirements relating to the administration of
incentive stock option plans, if any, of applicable securities laws and the Code
(collectively, the "Applicable Laws"), the Plan may (but need not) be
administered by different administrative bodies with respect to directors,
officers who are not directors and Employees who are neither directors nor
officers.

                           (ii) Administration with respect to Directors and
Officers. With respect to grants of Options to Employees or Consultants 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 Rule 16b-3 as
it applies to a plan intended to qualify thereunder as a discretionary plan and
Section 162(m) of the Code as it applies so as to qualify grants of Options to
Named Executives as performance-based compensation, or (B) a Committee
designated by the Board to administer the Plan, which Committee shall be
constituted in such a manner as to permit the Plan to comply with Rule 16b-3 as
it applies to a plan intended to qualify thereunder as a discretionary plan, to
qualify grants of Options to Named Executives as performance-based compensation
under Section 162(m) of the Code and otherwise so as to satisfy the Applicable
Laws.



 
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                           (iii) Administration with respect to Other Persons.
With respect to grants of Options 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 the Applicable Laws.

                           (iv) General. If a Committee has been appointed
pursuant to subsection (ii) or (iii) of this Section 4(a), 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 any 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 a Committee and thereafter directly administer the
Plan, all to the extent permitted by the Applicable Laws and, in the case of a
Committee appointed under subsection (ii), to the extent permitted by Rule 16b-3
as it applies to a plan intended to qualify thereunder as a discretionary plan,
and to the extent required under Section 162(m) of the Code to qualify grants of
Options to Named Executives as performance-based compensation.

                  (b) Powers of the Administrator. Subject to the provisions of
the Plan and in the case of a Committee, the specific duties delegated by the
Board to such Committee, 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(k) of the Plan;

                           (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 of Common
                  Stock 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, not
                  inconsistent with the terms of the Plan, of any award granted
                  hereunder (including, but not limited to, the share price and
                  any restriction or limitation);

                           (vii) to determine whether and under what
                  circumstances an Option may be settled in cash under Section
                  10(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 shall have declined
                  since the date the Option was granted.



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                  (c) 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. Eligibility.

                  (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 he or she is
otherwise eligible, be granted an additional Option or 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 designations, to the extent that the aggregate
Fair Market Value of the Shares with respect to which Options designated as
Incentive Stock Options are exercisable for the first time by any Optionee
during any calendar year (under all plans of the Company or any Parent or
Subsidiary) exceeds $100,000, such excess Options shall be treated as
Nonstatutory Stock Options.

                  (c) For purposes of Section 5(b), Incentive Stock Options
shall be taken into account in the order in which they were granted, and the
Fair Market Value of the Shares shall be determined as of the time the Option
with respect to such Shares is granted.

                  (d) The Plan shall not confer upon any Optionee any right with
respect to continuation of employment or consulting relationship with the
Company, nor shall it interfere in any way with an Optionee's right or the
Company's right to terminate his or her employment or consulting relationship at
any time, with or without cause.

         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
shareholders of the Company as described in Section 19 of the Plan. It shall
continue in effect for a term of ten (10) years unless sooner terminated under
Section 15 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 or such shorter term as may be
provided in the Option Agreement. However, in the case of an 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. Limitation on Grants to Employees. Subject to adjustment as provided
in Section 13 of this Plan, the maximum number of shares which may be subject to
Options granted to any one employee under this Plan for any fiscal year of the
Company shall be 750,000.




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         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 such price as is
determined by the Board, 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 the grant of such Incentive Stock 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 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
the 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 a person, who, at the time of
grant of such Option is a Named Executive of the Company, the per share exercise
price shall be no less than 100% of the Fair Market Value on the date of grant.

                                    (C) granted to any person other than those
persons described in subsections (ii) (A) and (B) above, the per Share exercise
price shall be no less than 85% of the Fair Market Value per Share on the date
of grant.

                  (b) Permissible Consideration. 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) and may
consist entirely 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)
authorization from the Company to retain from the total number of Shares as to
which the Option is exercised that number of Shares having a Fair Market Value
on the date of exercise equal to the exercise price for the total number of
Shares as to which the Option is exercised, (6) 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, (7) delivery of a subscription agreement for the Shares that
irrevocably



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obligates the option holder to take and pay for the Shares not more than twelve
months after the date of delivery of the subscription agreement, (8) any
combination of the foregoing methods of payment, or (9) such other consideration
and method of payment for the issuance of Shares to the extent permitted under
Applicable Laws. In making its determination as to the type of consideration to
accept, the Board shall consider if acceptance of such consideration may be
reasonably expected to benefit the Company.

         10. Exercise of Option.

                  (a) Procedure for Exercise; Rights as a Shareholder. Any
Option granted hereunder shall be exercisable at such times and under such
conditions as determined by the Board, 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 the Company has
received full payment for the Shares with respect to which the Option is
exercised. Full payment may, as authorized by the Board, consist of any
consideration and method of payment allowable under Section 9(b) 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. The Company shall issue (or cause to
be issued) such stock certificate promptly upon 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 13 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 Employment. In the event of termination of
an Optionee's consulting relationship or Continuous Status as an Employee with
the Company, such Optionee may, but only within three (3) months (or such other
period of time as is determined by the Board, with such determination in the
case of an Incentive Stock Option being made at the time of grant of the Option
and 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 Optionee
was entitled to exercise it at the date of such termination. To the extent that
Optionee was not entitled to ,exercise the Option at the date of such
termination, or if Optionee does not exercise such Option to the extent so
entitled within the time specified herein, the Option shall terminate.



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                  (c) Disability of Optionee. Notwithstanding the provisions of
Section 10(b) above, in the event of termination of an Optionee's consulting
relationship or Continuous Status as an Employee as a result of his or her total
and permanent disability (within the meaning of Section 22(e)(3) of the Code),
Optionee may, but only within twelve (12) months from 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 the Option to the extent
otherwise entitled to exercise it at the date of such termination. To the extent
that Optionee was not entitled to exercise the Option at the date of
termination, or if Optionee does not exercise such Option to the extent so
entitled within the time specified herein, the Option shall terminate.

                  (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 date of
the term of such Option as set forth in the Option Agreement), 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 the Optionee was entitled to exercise the
Option at the date of death. To the extent that the Optionee was not entitled to
exercise the Option at the date of termination, or if Optionee does not exercise
such Option to the extent so entitled within the time specified herein, the
Option shall terminate.

                  (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.

         11. Non-Transferability 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 and may be exercised,
during the lifetime of the Optionee, only by the Optionee.

         12. Stock Withholding to Satisfy Withholding Tax Obligation. At the
discretion of the Administrator. Optionees may satisfy withholding obligations
as provided in this paragraph. When an Optionee incurs tax liability in
connection with an Option, which tax liability is subject to tax withholding
under applicable tax laws, and the Optionee is obligated to pay the Company an
amount required to be withheld under applicable tax laws, the Optionee may
satisfy the withholding tax obligation by electing to have the Company withhold
from the Shares to be issued upon exercise of the Option 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 (the "Tax Date").



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         All elections by an Optionee to have Shares withheld for this purpose
shall be made in writing in a form acceptable to the Administrator and shall be
subject to the following restrictions:

                  (a) the election must be made on or prior to the applicable
Tax Date;

                  (b) once made, the election shall be irrevocable as to the
particular Shares of the Option as to which the election is made;

                  (c) all elections shall be subject to the consent or
disapproval of the Administrator;

                  (d) if the Optionee is subject to Section 16 of the Exchange
Act, the election must comply with the applicable provisions of Rule 16b-3 and
shall be subject to 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.

         In the event the election to have Shares withheld is made by an
Optionee and the Tax Date is deferred under Section 83 of the Code because no
election is filed under Section 83(b) of the Code, the Optionee shall receive
the full number of Shares with respect to which the Option or Stock Purchase
Right is exercised but, such Optionee shall be unconditionally obligated to
tender back to the Company the proper number of Shares on the Tax Date.

         13. Adjustments Upon Changes in Capitalization; Corporate Transactions.

                  (a) Changes in Capitalization. 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 that have
been authorized for issuance under the Plan but as to which no Options have yet
been granted or that have been returned to the Plan upon cancellation or
expiration of an Option, the maximum number of shares of Common Stock for which
Options may be granted to any employee under Section 8 of the Plan and 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 convertible into shares of stock
of any class, shall affect, and no adjustment by reason




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thereof shall be made with respect to, the number or price of shares of Common
Stock subject to an Option.

                  (b) Corporate Transactions. In the event of the proposed
dissolution or liquidation of the Company, the Board shall notify the Optionee
at least fifteen (15) days prior to such proposed action. To the extent it has
not been previously exercised, the Option will terminate immediately prior to
the consummation of such proposed action. In the event of a proposed sale of all
or substantially all of the assets of the Company, or the merger of the Company
with or into another corporation, the Option may be assumed or an equivalent
option may be substituted by such successor corporation or a parent or
subsidiary of such successor corporation. If the successor corporation does not
agree to assume the Option or substitute an equivalent option, the Board shall
notify the Optionee at least fifteen (15) days prior to the consummation of the
transaction. To the extent it has not been previously exercised, the Option will
terminate immediately prior to the consummation of such transaction.

         14. 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 Board. 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.

         15. 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, the following revisions or amendments shall require
approval of the shareholders of the Company in the manner described in Section
19 of the Plan:

                           (i) any increase in the number of Shares subject to
                  the Plan, other than an adjustment under Section 13 of the
                  Plan;

                           (ii) any change in the designation of the class of
                  persons eligible to be granted Options;

                           (iii) any change in the limitation on grants to
                  employees as described in Section 8 of the Plan or other
                  changes which would require shareholder approval to qualify
                  options granted hereunder as performance-based compensation
                  under Section 162(m) of the Code; or

                           (iv) any revision or amendment requiring shareholder
                  approval in order to preserve the qualification of the Plan
                  under Rule 16b-3.

                  (b) Shareholder Approval. If any amendment requiring
shareholder approval under Section 16(a) of the Plan is made subsequent to the
first registration of any class of equity




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securities by the Company under Section 12 of the Exchange Act, such shareholder
approval shall be solicited as described in Section 19 of the Plan.

                  (c) 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 Board, which agreement must be in writing and signed by the Optionee and the
Company.

         16. 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 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.

         17. 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.

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

         19. Shareholder Approval.

                  (a) Continuance of the Plan shall be subject to approval by
the shareholders of the Company within twelve (12) months before or after the
date the Plan is adopted. Such shareholder approval shall be obtained in the
degree and manner required under applicable state and federal law and the rules
of any stock exchange upon which the Shares are listed.

                  (b) In the event that the Company registers any class of
equity securities pursuant to Section 12 of the Exchange Act, any required
approval of the shareholders of the




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Company obtained after such registration shall be solicited substantially in
accordance with Section 14(a) of the Exchange Act and the rules and regulations
promulgated thereunder.

                  (c) If any required approval by the shareholders of the Plan
itself or of any amendment thereto is solicited at any time otherwise than in
the manner described in Section 19(b) hereof, then the Company shall, at or
prior to the first annual meeting of shareholders held subsequent to the later
of (1) the first registration of any class of equity securities of the Company
under Section 12 of the Exchange Act or (2) the granting of an Option hereunder
to an officer or director after such registration, do the following:

                           (i) furnish in writing to the holders entitled to
vote for the Plan substantially the same information that would be required (if
proxies to be voted with respect to approval or disapproval of the Plan or
amendment were then being solicited) by the rules and regulations in effect
under Section 14(a) of the Exchange Act at the time such information is
furnished; and

                           (ii) file with, or mail for filing to, the Securities
and Exchange Commission four copies of the written information referred to in
subsection (i) hereof not later than the date on which such information is first
sent or given to shareholders.

         20. Information to Optionees. The Company shall provide to each
Optionee and individual who acquired shares pursuant to the exercise of an
option, during the period for which such Optionee has one or more Options
outstanding, copies of all annual reports and other information that are
provided to all shareholders of the Company.



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                                   SCHEDULE II

                                     ISOCOR

                        VALUATION AND QUALIFYING ACCOUNTS
                                 (IN THOUSANDS)




                                         BALANCE AT     CHARGED TO                     BALANCE AT
                                          BEGINNING     COSTS AND                        END
       ACCOUNT DESCRIPTION                OF PERIOD      EXPENSES      DEDUCTIONS      OF PERIOD
- -----------------------------------       ---------      --------      ----------      ---------
                                                                          
Year ended December 31, 1994
  Allowance for doubtful accounts,
     returns, and price protection         $(152)        $  (344)        $  202        $  (294)
Year ended December 31, 1995
  Allowance for doubtful accounts,
     returns, and price protection         $(294)        $  (557)        $  265        $  (586)
Year ended December 31, 1996,
  Allowance for doubtful accounts,
     returns, and price protection         $(586)        $(2,771)        $1,710        $(1,647)



        STATEMENT OF COMPUTATION OF SHARES USED IN PER SHARE COMPUTATION
                                 (IN THOUSANDS)




                                                              December 31,     December 31,    December 31,
                                                                     1994             1995            1996
                                                                     ----             ----            ----
                                                                                      
Computation of shares used in net income (loss) per share:
     Weighted average common shares outstanding ..........          1,618            1,663           7,258
     Common equivalent shares attributable to stock
       options (treasury stock method) ...................            178              938             989
     Common equivalent shares attributable to redeemable
       preferred stock ...................................            813            5,182              --
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Shares used in per share calculation .....................          2,609            7,783           8,247
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