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                                                                    EXHIBIT 10.1

                           OCEN COMMUNICATIONS, INC.
                     1998 STOCK OPTION/STOCK ISSUANCE PLAN

                                  ARTICLE ONE

                              GENERAL PROVISIONS
                              ------------------

          I.   PURPOSE OF THE PLAN

               This 1998 Stock Option/Stock Issuance Plan is intended to promote
the interests of oCen Communications, Inc., a California, by providing eligible
persons in the Corporation's employ or service with the opportunity to acquire a
proprietary interest, or otherwise increase their proprietary interest, in the
Corporation as an incentive for them to continue in such employ or service.

               Capitalized terms herein shall have the meanings assigned to such
terms in the attached Appendix.

          II.  STRUCTURE OF THE PLAN

               A. The Plan shall be divided into two (2) separate equity
programs:

                         (i)  the Option Grant Program under which eligible
     persons may, at the discretion of the Plan Administrator, be granted
     options to purchase shares of Common Stock, and

                         (ii) the Stock Issuance Program under which eligible
     persons may, at the discretion of the Plan Administrator, be issued shares
     of Common Stock directly, either through the immediate purchase of such
     shares or as a bonus for services rendered the Corporation (or any Parent
     or Subsidiary).

               B. The provisions of Articles One and Four shall apply to both
equity programs under the Plan and shall accordingly govern the interests of all
persons under the Plan.

     III.  ADMINISTRATION OF THE PLAN

           A.  The Plan shall be administered by the Board.  However, any or all
administrative functions otherwise exercisable by the Board may be delegated to
the Committee.  Members of the Committee shall serve for such period of time as
the Board may determine and shall be subject to removal by the Board at any
time.  The Board may also at any time terminate the functions of the Committee
and reassume all powers and authority previously delegated to the Committee.
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               B.  The Plan Administrator shall have full power and authority
(subject to the provisions of the Plan) to establish such rules and regulations
as it may deem appropriate for proper administration of the Plan and to make
such determinations under, and issue such interpretations of, the Plan and any
outstanding options or stock issuances thereunder as it may deem necessary or
advisable. Decisions of the Plan Administrator shall be final and binding on all
parties who have an interest in the Plan or any option or stock issuance
thereunder.

          IV.  ELIGIBILITY

               A.  The persons eligible to participate in the Plan are as
follows:

                         (i)   Employees,

                         (ii)  non-employee members of the Board or the non-
     employee members of the board of directors of any Parent or Subsidiary, and

                         (iii) consultants and other independent advisors who
     provide services to the Corporation (or any Parent or Subsidiary).

               B.  The Plan Administrator shall have full authority to
determine, (i) with respect to the grants made under the Option Grant Program,
which eligible persons are to receive the option grants, the time or times when
those grants are to be made, the number of shares to be covered by each such
grant, the status of the granted option as either an Incentive Option or a Non-
Statutory Option, the time or times when each option is to become exercisable,
the vesting schedule (if any) applicable to the option shares and the maximum
term for which the option is to remain outstanding, and (ii) with respect to
stock issuances made under the Stock Issuance Program, which eligible persons
are to receive such stock issuances, the time or times when those issuances are
to be made, the number of shares to be issued to each Participant, the vesting
schedule (if any) applicable to the issued shares and the consideration to be
paid by the Participant for such shares.

               C.  The Plan Administrator shall have the absolute discretion
either to grant options in accordance with the Option Grant Program or to effect
stock issuances in accordance with the Stock Issuance Program.

          V.   STOCK SUBJECT TO THE PLAN

               A.  The stock issuable under the Plan shall be shares of
authorized but unissued or reacquired Common Stock. The maximum number of shares
of Common Stock which may be issued over the term of the Plan shall not exceed
2,611,200/1/ shares.

               B.  Shares of Common Stock subject to outstanding options shall
be available for subsequent issuance under the Plan to the extent (i) the
options expire or terminate

______________________

     /1/ Adjusted for 3-1 forward split of the Common Stock, as approved by the
Board of Directors on January 8, 1999.

                                      2.
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for any reason prior to exercise in full or (ii) the options are cancelled in
accordance with the cancellation-regrant provisions of Article Two. Unvested
shares issued under the Plan and subsequently repurchased by the Corporation, at
the option exercise or direct issue price paid per share, pursuant to the
Corporation's repurchase rights under the Plan shall be added back to the number
of shares of Common Stock reserved for issuance under the Plan and shall
accordingly be available for reissuance through one or more subsequent option
grants or direct stock issuances under the Plan.

               C.  Should any change be made to the Common Stock by reason of
any stock split, stock dividend, recapitalization, combination of shares,
exchange of shares or other change affecting the outstanding Common Stock as a
class without the Corporation's receipt of consideration, appropriate
adjustments shall be made to (i) the maximum number and/or class of securities
issuable under the Plan and (ii) the number and/or class of securities and the
exercise price per share in effect under each outstanding option in order to
prevent the dilution or enlargement of benefits thereunder. The adjustments
determined by the Plan Administrator shall be final, binding and conclusive. In
no event shall any such adjustments be made in connection with the conversion of
one or more outstanding shares of the Corporation's preferred stock into shares
of Common Stock.

                                      3.
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                                  ARTICLE TWO

                             OPTION GRANT PROGRAM

          I.   OPTION TERMS

               Each option shall be evidenced by one or more documents in the
form approved by the Plan Administrator; provided, however, that each such
document shall comply with the terms specified below. Each document evidencing
an Incentive Option shall, in addition, be subject to the provisions of the Plan
applicable to such options.

               A.   Exercise Price.
                    --------------

                    1.  The exercise price per share shall be fixed by the Plan
     Administrator in accordance with the following provisions:

                         (i)  The exercise price per share shall not be less
     than eighty-five percent (85%) of the Fair Market Value per share of Common
     Stock on the option grant date.

                         (ii) If the person to whom the option is granted is a
     10% Shareholder, then the exercise price per share shall not be less than
     one hundred ten percent (110%) of the Fair Market Value per share of Common
     Stock on the option grant date.

                    2.   The exercise price shall become immediately due upon
exercise of the option and shall, subject to the provisions of Section I of
Article Four and the documents evidencing the option, be payable in cash or
check made payable to the Corporation. Should the Common Stock be registered
under Section 12 of the 1934 Act at the time the option is exercised, then the
exercise price may also be paid as follows:

                         (i)  in shares of Common Stock held for the requisite
     period necessary to avoid a charge to the Corporation's earnings for
     financial reporting purposes and valued at Fair Market Value on the
     Exercise Date, or

                         (ii) to the extent the option is exercised for vested
     shares, through a special sale and remittance procedure pursuant to which
     the Optionee shall concurrently provide irrevocable instructions (A) to a
     Corporation-designated brokerage firm to effect the immediate sale of the
     purchased shares and remit to the Corporation, out of the sale proceeds
     available on the settlement date, sufficient funds to cover the aggregate
     exercise price payable for the purchased shares plus all applicable
     Federal, state and local income and employment taxes required to be
     withheld by the Corporation by

                                      4.
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     reason of such exercise and (B) to the Corporation to deliver the
     certificates for the purchased shares directly to such brokerage firm in
     order to complete the sale.

               Except to the extent such sale and remittance procedure is
utilized, payment of the exercise price for the purchased shares must be made on
the Exercise Date.

               B.   Exercise and Term of Options. Each option shall be
                    ----------------------------
exercisable at such time or times, during such period and for such number of
shares as shall be determined by the Plan Administrator and set forth in the
documents evidencing the option grant. However, no option shall have a term in
excess of ten (10) years measured from the option grant date.

               C.   Effect of Termination of Service.
                    --------------------------------

                    1.   The following provisions shall govern the exercise of
any options held by the Optionee at the time of cessation of Service or death:

                         (i)   Should the Optionee cease to remain in Service
     for any reason other than death, Disability or Misconduct, then the period
     during which each such outstanding option may be exercised shall be limited
     to the three (3) month period measured from the date of such cessation of
     Service.

                         (ii)  Should Optionee's Service terminate by reason of
     Disability, then period during which each such outstanding option may be
     exercised shall be limited to the twelve (12)-month period measured from
     the date of such cessation of Service.

                         (iii) If the Optionee dies while holding an outstanding
option, then the personal representative of his or her estate or the person or
persons to whom the option is transferred pursuant to the Optionee's will or the
laws of inheritance shall have a twelve (12)-month period following the date of
the Optionee's death to exercise such option.

                         (iv)  Under no circumstances, however, shall any such
     option be exercisable after the specified expiration of the option term.

                         (v)   During the applicable post-Service exercise
     period, the option may not be exercised in the aggregate for more than the
     number of vested shares for which the option is exercisable on the date of
     the Optionee's cessation of Service. Upon the expiration of the applicable
     exercise period or (if earlier) upon the expiration of the option term, the
     option shall terminate and cease to be outstanding for any vested shares
     for which the option has not been exercised. However, the option shall,
     immediately upon the Optionee's cessation of Service, terminate and cease
     to be outstanding with respect to any and all option shares for which the
     option is not otherwise at the time exercisable or in which the Optionee is
     not otherwise at that time vested.

                                      5.
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                         (vi)  Should Optionee's Service be terminated for
     Misconduct, then all outstanding options held by the Optionee shall
     terminate immediately and cease to remain outstanding.

                    2.   The Plan Administrator shall have the discretion,
     exercisable either at the time an option is granted or at any time while
     the option remains outstanding, to:

                         (i)   extend the period of time for which the option is
     to remain exercisable following Optionee's cessation of Service or death
     from the limited period otherwise in effect for that option to such greater
     period of time as the Plan Administrator shall deem appropriate, but in no
     event beyond the expiration of the option term, and/or

                         (ii)  permit the option to be exercised, during the
     applicable post-Service exercise period, not only with respect to the
     number of vested shares of Common Stock for which such option is
     exercisable at the time of the Optionee's cessation of Service but also
     with respect to one or more additional installments in which the Optionee
     would have vested under the option had the Optionee continued in Service.

               D.   Shareholder Rights. The holder of an option shall have no
                    ------------------
shareholder rights with respect to the shares subject to the option until such
person shall have exercised the option, paid the exercise price and become the
holder of record of the purchased shares.

               E.   Unvested Shares. The Plan Administrator shall have the
                    ---------------
discretion to grant options which are exercisable for unvested shares of Common
Stock. Should the Optionee cease Service while holding such unvested shares, the
Corporation shall have the right to repurchase, at the exercise price paid per
share, any or all of those unvested shares. The terms upon which such repurchase
right shall be exercisable (including the period and procedure for exercise and
the appropriate vesting schedule for the purchased shares) shall be established
by the Plan Administrator and set forth in the document evidencing such
repurchase right. The Plan Administrator may not impose a vesting schedule upon
the option grant or any shares of Common Stock subject to that option which is
more restrictive than twenty percent (20%) per year vesting, with the initial
vesting to occur not later than one (1) year after the option grant date.
However, such limitation shall not be applicable to any option grants made to
individuals who are officers of the Corporation, non-employee Board members or
independent consultants.

               F.  First Refusal Rights. Until such time as the Common Stock is
                   --------------------
first registered under Section 12 of the 1934 Act, the Corporation shall have
the right of first refusal with respect to any proposed disposition by the
Optionee (or any successor in interest) of any shares of Common Stock issued
under the Plan. Such right of first refusal shall be exercisable in accordance
with the terms established by the Plan Administrator and set forth in the
document evidencing such right.

                                      6.
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               G.   Limited Transferability of Options. During the lifetime of
                    ----------------------------------
the Optionee, Incentive Options shall be exercisable only by the Optionee and
shall not be assignable or transferable other than by will or by the laws of
descent and distribution following the Optionee's death.

               H.   Withholding. The Corporation's obligation to deliver shares
                    -----------
of Common Stock upon the exercise of any options granted under the Plan shall be
subject to the satisfaction of all applicable Federal, state and local income
and employment tax withholding requirements.

          II.  INCENTIVE OPTIONS

               The terms specified below shall be applicable to all Incentive
Options.  Except as modified by the provisions of this Section II, all the
provisions of the Plan shall be applicable to Incentive Options.  Options which
are specifically designated as Non-Statutory Options shall not be subject to the
terms of this Section II.

               A.   Eligibility. Incentive Options may only be granted to
                    -----------
Employees.

               B.   Exercise Price. The exercise price per share shall not be
                    --------------
less than one hundred percent (100%) of the Fair Market Value per share of
Common Stock on the option grant date.

               C.   Dollar Limitation. The aggregate Fair Market Value of the
                    -----------------
shares of Common Stock (determined as of the respective date or dates of grant)
for which one or more options granted to any Employee under the Plan (or any
other option plan of the Corporation or any Parent or Subsidiary) may for the
first time become exercisable as Incentive Options during any one (1) calendar
year shall not exceed the sum of One Hundred Thousand Dollars ($100,000). To the
extent the Employee holds two (2) or more such options which become exercisable
for the first time in the same calendar year, the foregoing limitation on the
exercisability of such options as Incentive Options shall be applied on the
basis of the order in which such options are granted.

               D.   10% Shareholder. If any Employee to whom an Incentive Option
                    ---------------
is granted is a 10% Shareholder, then the option term shall not exceed five (5)
years measured from the option grant date.

                                      7.
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          III. CORPORATE TRANSACTION

               A.  The shares subject to each option outstanding under the Plan
at the time of a Corporate Transaction shall automatically vest in full so that
each such option shall, immediately prior to the effective date of the Corporate
Transaction, become fully exercisable for all of the shares of Common Stock at
the time subject to that option and may be exercised for any or all of those
shares as fully-vested shares of Common Stock. However, the shares subject to an
outstanding option shall not vest on such an accelerated basis if and to the
extent: (i) such option is assumed by the successor corporation (or parent
thereof) in the Corporate Transaction and the Corporation's repurchase rights
with respect to the unvested option shares are concurrently assigned to such
successor corporation (or parent thereof) or (ii) such option is to be replaced
with a cash incentive program of the successor corporation which preserves the
spread existing on the unvested option shares at the time of the Corporate
Transaction and provides for subsequent payout in accordance with the same
vesting schedule applicable to those unvested option shares or (iii) the
acceleration of such option is subject to other limitations imposed by the Plan
Administrator at the time of the option grant.

               B.  All outstanding repurchase rights shall also terminate
automatically, and the shares of Common Stock subject to those terminated rights
shall immediately vest in full, in the event of any Corporate Transaction,
except to the extent: (i) those repurchase rights are assigned to the successor
corporation (or parent thereof) in connection with such Corporate Transaction or
(ii) such accelerated vesting is precluded by other limitations imposed by the
Plan Administrator at the time the repurchase right is issued.

               C.  Immediately following the consummation of the Corporate
Transaction, all outstanding options shall terminate and cease to be
outstanding, except to the extent assumed by the successor corporation (or
parent thereof).

               D.  Each option which is assumed in connection with a Corporate
Transaction shall be appropriately adjusted, immediately after such Corporate
Transaction, to apply to the number and class of securities which would have
been issuable to the Optionee in consummation of such Corporate Transaction, had
the option been exercised immediately prior to such Corporate Transaction.
Appropriate adjustments shall also be made to (i) the number and class of
securities available for issuance under the Plan following the consummation of
such Corporate Transaction and (ii) the exercise price payable per share under
each outstanding option, provided the aggregate exercise price payable for such
securities shall remain the same.

               E.  The Plan Administrator shall have the discretion, exercisable
either at the time the option is granted or at any time while the option remains
outstanding, to provide for the automatic acceleration (in whole or in part) of
one or more outstanding options (and the immediate termination of the
Corporation's repurchase rights with respect to the shares subject to those
options) upon the occurrence of a Corporate Transaction, whether or not those
options are to be assumed in the Corporate Transaction.

                                      8.
<PAGE>

               F.  The Plan Administrator shall also have full power and
authority, exercisable either at the time the option is granted or at any time
while the option remains outstanding, to structure such option so that the
shares subject to that option will automatically vest on an accelerated basis
should the Optionee's Service terminate by reason of an Involuntary Termination
within a designated period (not to exceed eighteen (18) months) following the
effective date of any Corporate Transaction in which the option is assumed and
the repurchase rights applicable to those shares do not otherwise terminate. Any
option so accelerated shall remain exercisable for the fully-vested option
shares until the earlier of (i) the expiration of the option term or (ii) the
expiration of the one (1)-year period measured from the effective date of the
Involuntary Termination. In addition, the Plan Administrator may provide that
one or more of the Corporation's outstanding repurchase rights with respect to
shares held by the Optionee at the time of such Involuntary Termination shall
immediately terminate on an accelerated basis, and the shares subject to those
terminated rights shall accordingly vest at that time.

               G.  The portion of any Incentive Option accelerated in connection
with a Corporate Transaction shall remain exercisable as an Incentive Option
only to the extent the applicable One Hundred Thousand Dollar limitation is not
exceeded. To the extent such dollar limitation is exceeded, the accelerated
portion of such option shall be exercisable as a Non-Statutory Option under the
Federal tax laws.

               H.  The grant of options under the Plan shall in no way affect
the right of the Corporation to adjust, reclassify, reorganize or otherwise
change its capital or business structure or to merge, consolidate, dissolve,
liquidate or sell or transfer all or any part of its business or assets.

          IV.  CANCELLATION AND REGRANT OF OPTIONS

               The Plan Administrator shall have the authority to effect, at any
time and from time to time, with the consent of the affected option holders, the
cancellation of any or all outstanding options under the Plan and to grant in
substitution therefor new options covering the same or different number of
shares of Common Stock but with an exercise price per share based on the Fair
Market Value per share of Common Stock on the new option grant date.

                                      9.
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                                 ARTICLE THREE

                            STOCK ISSUANCE PROGRAM


          I.   STOCK ISSUANCE TERMS

               Shares of Common Stock may be issued under the Stock Issuance
Program through direct and immediate issuances without any intervening option
grants. Each such stock issuance shall be evidenced by a Stock Issuance
Agreement which complies with the terms specified below.

               A.   Purchase Price.
                    --------------

                    1.  The purchase price per share shall be fixed by the Plan
     Administrator but shall not be less than eighty-five percent (85%) of the
     Fair Market Value per share of Common Stock on the issue date. However, the
     purchase price per share of Common Stock issued to a 10% Shareholder shall
     not be less than one hundred and ten percent (110%) of such Fair Market
     Value.

                    2.  Subject to the provisions of Section I of Article Four,
     shares of Common Stock may be issued under the Stock Issuance Program for
     any of the following items of consideration which the Plan Administrator
     may deem appropriate in each individual instance:

                        (i)  cash or check made payable to the Corporation, or

                        (ii) past services rendered to the Corporation (or any
     Parent or Subsidiary).

               B.   Vesting Provisions.
                    ------------------

                    1.  Shares of Common Stock issued under the Stock Issuance
Program may, in the discretion of the Plan Administrator, be fully and
immediately vested upon issuance or may vest in one or more installments over
the Participant's period of Service or upon attainment of specified performance
objectives. However, the Plan Administrator may not impose a vesting schedule
upon any stock issuance effected under the Stock Issuance Program which is more
restrictive than twenty percent (20%) per year vesting, with initial vesting to
occur not later than one (1) year after the issuance date. Such limitation shall
not apply to any Common Stock issuances made to the officers of the Corporation,
non-employee Board members or independent consultants.

                                      10.
<PAGE>

          2.  Any new, substituted or additional securities or other property
(including money paid other than as a regular cash dividend) which the
Participant may have the right to receive with respect to the Participant's
unvested shares of Common Stock by reason of any stock dividend, stock split,
recapitalization, combination of shares, exchange of shares or other change
affecting the outstanding Common Stock as a class without the Corporation's
receipt of consideration shall be issued subject to (i) the same vesting
requirements applicable to the Participant's unvested shares of Common Stock and
(ii) such escrow arrangements as the Plan Administrator shall deem appropriate.

          3.  The Participant shall have full shareholder rights with respect to
any shares of Common Stock issued to the Participant under the Stock Issuance
Program, whether or not the Participant's interest in those shares is vested.
Accordingly, the Participant shall have the right to vote such shares and to
receive any regular cash dividends paid on such shares.

          4.  Should the Participant cease to remain in Service while holding
one or more unvested shares of Common Stock issued under the Stock Issuance
Program or should the performance objectives not be attained with respect to one
or more such unvested shares of Common Stock, then those shares shall be
immediately surrendered to the Corporation for cancellation, and the Participant
shall have no further shareholder rights with respect to those shares. To the
extent the surrendered shares were previously issued to the Participant for
consideration paid in cash or cash equivalent (including the Participant's
purchase-money indebtedness), the Corporation shall repay to the Participant the
cash consideration paid for the surrendered shares and shall cancel the unpaid
principal balance of any outstanding purchase-money note of the Participant
attributable to such surrendered shares.

          5.  The Plan Administrator may in its discretion waive the surrender
and cancellation of one or more unvested shares of Common Stock (or other assets
attributable thereto) which would otherwise occur upon the non-completion of the
vesting schedule applicable to such shares. Such waiver shall result in the
immediate vesting of the Participant's interest in the shares of Common Stock as
to which the waiver applies. Such waiver may be effected at any time, whether
before or after the Participant's cessation of Service or the attainment or non-
attainment of the applicable performance objectives.

          6.  First Refusal Rights. Until such time as the Common Stock is first
registered under Section 12 of the 1934 Act, the Corporation shall have the
right of first refusal with respect to any proposed disposition by the
Participant (or any successor in interest) of any shares of Common Stock issued
under the Stock Issuance Program. Such right of first refusal shall be
exercisable in accordance with the terms established by the Plan Administrator
and set forth in the document evidencing such right.

                                      11.
<PAGE>

          II.  CORPORATE TRANSACTION

               A.  Upon the occurrence of a Corporate Transaction, all
outstanding repurchase rights under the Stock Issuance Program shall terminate
automatically, and the shares of Common Stock subject to those terminated rights
shall immediately vest in full, except to the extent: (i) those repurchase
rights are assigned to the successor corporation (or parent thereof) in
connection with such Corporate Transaction or (ii) such accelerated vesting is
precluded by other limitations imposed by the Plan Administrator at the time the
repurchase right is issued.

               B.  The Plan Administrator shall have the discretionary
authority, exercisable either at the time the unvested shares are issued or any
time while the Corporation's repurchase rights with respect to those shares
remain outstanding, to provide that those rights shall automatically terminate
on an accelerated basis, and the shares of Common Stock subject to those
terminated rights shall immediately vest, in the event the Participant's Service
should subsequently terminate by reason of an Involuntary Termination within a
designated period (not to exceed eighteen (18) months) following the effective
date of any Corporate Transaction in which those repurchase rights are assigned
to the successor corporation (or parent thereof).

          III. SHARE ESCROW/LEGENDS

               Unvested shares may, in the Plan Administrator's discretion, be
held in escrow by the Corporation until the Participant's interest in such
shares vests or may be issued directly to the Participant with restrictive
legends on the certificates evidencing those unvested shares.

                                      12.
<PAGE>

                                 ARTICLE FOUR


                                 MISCELLANEOUS

          I.   FINANCING

               The Plan Administrator may permit any Optionee or Participant to
pay the option exercise price or the purchase price for shares issued to such
person under the Plan by delivering a full-recourse, interest-bearing promissory
note payable in one or more installments and secured by the purchased shares.
However, any promissory note delivered by a consultant must be secured by
collateral in addition to the purchased shares of Common Stock. In no event
shall the maximum credit available to the Optionee or Participant exceed the sum
of (i) the aggregate option exercise price or purchase price payable for the
purchased shares plus (ii) any Federal, state and local income and employment
tax liability incurred by the Optionee or the Participant in connection with the
option exercise or share purchase.

          II.  EFFECTIVE DATE AND TERM OF PLAN

               A.  The Plan became effective upon its adoption by the Board on
August 10, 1998, but no option granted under the Plan may be exercised, and no
shares shall be issued under the Plan, until the Plan is approved by the
Corporation's shareholders. If such shareholder approval is not obtained within
twelve (12) months after the date of the Board's adoption of the Plan, then all
options previously granted under the Plan shall terminate and cease to be
outstanding, and no further options shall be granted and no shares shall be
issued under the Plan. Subject to such limitation, the Plan Administrator may
grant options and issue shares under the Plan at any time after the effective
date of the Plan and before the date fixed herein for termination of the Plan.

               B.  The Plan shall terminate upon the earliest of (i) August 10,
2008, (ii) the date on which all shares available for issuance under the Plan
shall have been issued as vested shares or (iii) the termination of all
outstanding options in connection with a Corporate Transaction. All options and
unvested stock issuances outstanding at that time under the Plan shall continue
to have full force and effect in accordance with the provisions of the documents
evidencing such options or issuances.

          III. AMENDMENT OF THE PLAN

               A.  The Board shall have complete and exclusive power and
authority to amend or modify the Plan in any or all respects. However, no such
amendment or modification shall adversely affect the rights and obligations with
respect to options or unvested stock issuances at the time outstanding under the
Plan unless the Optionee or the Participant consents to such amendment or
modification. In addition, certain amendments may require shareholder approval
pursuant to applicable laws and regulations.

                                      13.
<PAGE>

               B.  Options may be granted under the Option Grant Program and
shares may be issued under the Stock Issuance Program which are in each instance
in excess of the number of shares of Common Stock then available for issuance
under the Plan, provided any excess shares actually issued under those programs
shall be held in escrow until there is obtained shareholder approval of an
amendment sufficiently increasing the number of shares of Common Stock available
for issuance under the Plan. If such shareholder approval is not obtained within
twelve (12) months after the date the first such excess issuances are made, then
(i) any unexercised options granted on the basis of such excess shares shall
terminate and cease to be outstanding and (ii) the Corporation shall promptly
refund to the Optionees and the Participants the exercise or purchase price paid
for any excess shares issued under the Plan and held in escrow, together with
interest (at the applicable Short Term Federal Rate) for the period the shares
were held in escrow, and such shares shall thereupon be automatically cancelled
and cease to be outstanding.

          IV.  USE OF PROCEEDS

               Any cash proceeds received by the Corporation from the sale of
shares of Common Stock under the Plan shall be used for general corporate
purposes.

          V.   WITHHOLDING

               The Corporation's obligation to deliver shares of Common Stock
upon the exercise of any options or upon the issuance or vesting of any shares
issued under the Plan shall be subject to the satisfaction of all applicable
Federal, state and local income and employment tax withholding requirements.

          VI.  REGULATORY APPROVALS

               The implementation of the Plan, the granting of any options under
the Plan and the issuance of any shares of Common Stock (i) upon the exercise of
any option or (ii) under the Stock Issuance Program shall be subject to the
Corporation's procurement of all approvals and permits required by regulatory
authorities having jurisdiction over the Plan, the options granted under it and
the shares of Common Stock issued pursuant to it.

          VII. NO EMPLOYMENT OR SERVICE RIGHTS

               Nothing in the Plan shall confer upon the Optionee or the
Participant any right to continue in Service for any period of specific duration
or interfere with or otherwise restrict in any way the rights of the Corporation
(or any Parent or Subsidiary employing or retaining such person) or of the
Optionee or the Participant, which rights are hereby expressly reserved by each,
to terminate such person's Service at any time for any reason, with or without
cause.

                                      14.
<PAGE>

          VIII.  FINANCIAL REPORTS

                 The Corporation shall deliver a balance sheet and an income
statement at least annually to each individual holding an outstanding option
under the Plan, unless such individual is a key Employee whose duties in
connection with the Corporation (or any Parent or Subsidiary) assure such
individual access to equivalent information.

                                      15.
<PAGE>

                                   APPENDIX

               The following definitions shall be in effect under the Plan:

          A.   Board shall mean the Corporation's Board of Directors.
               -----

          B.   Code shall mean the Internal Revenue Code of 1986, as amended.
               ----

          C.   Committee shall mean a committee of two (2) or more Board
               ---------
members appointed by the Board to exercise one or more administrative functions
under the Plan.

          D.   Common Stock shall mean the Corporation's common stock.
               ------------

          E.   Corporate Transaction shall mean either of the following
               ---------------------
shareholder-approved transactions to which the Corporation is a party:

                    (i)  a merger or consolidation in which securities
     possessing more than fifty percent (50%) of the total combined voting power
     of the Corporation's outstanding securities are transferred to a person or
     persons different from the persons holding those securities immediately
     prior to such transaction, or

                    (ii) the sale, transfer or other disposition of all or
     substantially all of the Corporation's assets in complete liquidation or
     dissolution of the Corporation.

          F.   Corporation shall mean oCen Communications, Inc., a California
               -----------
corporation, and any successor corporation to all or substantially all of the
assets or voting stock of oCen Communications, Inc. which shall by appropriate
action adopt the Plan.

          G.   Disability  shall mean the inability of the Optionee or the
               ----------
Participant to engage in any substantial gainful activity by reason of any
medically determinable physical or mental impairment and shall be determined by
the Plan Administrator on the basis of such medical evidence as the Plan
Administrator deems warranted under the circumstances.

          H.   Employee shall mean an individual who is in the employ of the
               --------
Corporation (or any Parent or Subsidiary), subject to the control and direction
of the employer entity as to both the work to be performed and the manner and
method of performance.

          I.   Exercise Date shall mean the date on which the Corporation shall
               -------------
have received written notice of the option exercise.

                                     A-1.
<PAGE>

          J.   Fair Market Value per share of Common Stock on any relevant date
               -----------------
shall be determined in accordance with the following provisions:

                    (i)   If the Common Stock is at the time traded on the
     Nasdaq National Market, then the Fair Market Value shall be the closing
     selling price per share of Common Stock on the date in question, as such
     price is reported by the National Association of Securities Dealers on the
     Nasdaq National Market. If there is no closing selling price for the Common
     Stock on the date in question, then the Fair Market Value shall be the
     closing selling price on the last preceding date for which such quotation
     exists.

                    (ii)  If the Common Stock is at the time listed on any Stock
     Exchange, then the Fair Market Value shall be the closing selling price per
     share of Common Stock on the date in question on the Stock Exchange
     determined by the Plan Administrator to be the primary market for the
     Common Stock, as such price is officially quoted in the composite tape of
     transactions on such exchange. If there is no closing selling price for the
     Common Stock on the date in question, then the Fair Market Value shall be
     the closing selling price on the last preceding date for which such
     quotation exists.

                    (iii) If the Common Stock is at the time neither listed on
any Stock Exchange nor traded on the Nasdaq National Market, then the Fair
Market Value shall be determined by the Plan Administrator after taking into
account such factors as the Plan Administrator shall deem appropriate.

          K.   Incentive Option shall mean an option which satisfies the
               ----------------
requirements of Code Section 422.

          L.   Involuntary Termination shall mean the termination of the
               -----------------------
Service of any individual which occurs by reason of:

                    (i)  such individual's involuntary dismissal or discharge by
     the Corporation for reasons other than Misconduct, or

                    (ii) such individual's voluntary resignation following (A) a
     change in his or her position with the Corporation which materially reduces
     his or her duties and responsibilities or the level of management to which
     he or she reports, (B) a reduction in his or her level of compensation
     (including base salary, fringe benefits and target bonuses under any
     corporate-performance based bonus or incentive programs) by more than
     fifteen percent (15%) or (C) a relocation of such individual's place of
     employment by more than fifty (50) miles, provided and only if such change,
     reduction or relocation is effected without the individual's consent.

                                     A-2.
<PAGE>

          M.   Misconduct shall mean the commission of any act of fraud,
               ----------
embezzlement or dishonesty by the Optionee or Participant, any unauthorized use
or disclosure by such person of confidential information or trade secrets of the
Corporation (or any Parent or Subsidiary), or any other intentional misconduct
by such person adversely affecting the business or affairs of the Corporation
(or any Parent or Subsidiary) in a material manner. The foregoing definition
shall not be deemed to be inclusive of all the acts or omissions which the
Corporation (or any Parent or Subsidiary) may consider as grounds for the
dismissal or discharge of any Optionee, Participant or other person in the
Service of the Corporation (or any Parent or Subsidiary).

          N.   1934 Act shall mean the Securities Exchange Act of 1934, as
               --------
amended.

          O.   Non-Statutory Option shall mean an option not intended to
               --------------------
satisfy the requirements of Code Section 422.

          P.   Option Grant Program shall mean the option grant program in
               --------------------
effect under the Plan.

          Q.   Optionee shall mean any person to whom an option is granted
               --------
under the Plan.

          R.   Parent shall mean any corporation (other than the Corporation)
               ------
in an unbroken chain of corporations ending with the Corporation, provided each
corporation in the unbroken chain (other than the Corporation) owns, at the time
of the determination, stock possessing fifty percent (50%) or more of the total
combined voting power of all classes of stock in one of the other corporations
in such chain.

          S.   Participant shall mean any person who is issued shares of Common
               -----------
Stock under the Stock Issuance Program.

          T.   Plan shall mean the Corporation's 1998 Stock Option/Stock
               ----
Issuance Plan, as set forth in this document.

          U.   Plan Administrator shall mean either the Board or the Committee
               ------------------
acting in its capacity as administrator of the Plan.

          V.   Service shall mean the provision of services to the Corporation
               -------
(or any Parent or Subsidiary) by a person in the capacity of an Employee, a
non--employee member of the board of directors or a consultant or independent
advisor, except to the extent otherwise specifically provided in the documents
evidencing the option grant.

          W.   Stock Exchange shall mean either the American Stock Exchange or
               --------------
the New York Stock Exchange.

          X.   Stock Issuance Agreement shall mean the agreement entered into
               ------------------------
by the Corporation and the Participant at the time of issuance of shares of
Common Stock under the Stock Issuance Program.

                                     A-3.
<PAGE>

          Y.   Stock Issuance Program shall mean the stock issuance program in
               ----------------------
effect under the Plan.

          Z.   Subsidiary shall mean any corporation (other than the
               ----------
Corporation) in an unbroken chain of corporations beginning with the
Corporation, provided each corporation (other than the last corporation) in the
unbroken chain owns, at the time of the determination, stock possessing fifty
percent (50%) or more of the total combined voting power of all classes of stock
in one of the other corporations in such chain.

          AA.  10% Shareholder shall mean the owner of stock (as determined
               ---------------
under Code Section 424(d)) possessing more than ten percent (10%) of the total
combined voting power of all classes of stock of the Corporation (or any Parent
or Subsidiary).

                                     A-4.