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                                                                    EXHIBIT 4.6


                                           AS AMENDED THROUGH FEBRUARY 29, 2000

                               MESSAGEMEDIA, INC.
                          EMPLOYEE STOCK PURCHASE PLAN


I.       PURPOSE OF THE PLAN

This Employee Stock Purchase Plan is intended to promote the interests of
MessageMedia, Inc. by providing eligible employees with the opportunity to
acquire a proprietary interest in the Corporation through participation in a
payroll-deduction based employee stock purchase plan designed to qualify under
Section 423 of the Code.

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

II.      ADMINISTRATION OF THE PLAN

The Plan Administrator shall have full authority to interpret and construe any
provision of the Plan and to adopt such rules and regulations for administering
the Plan as it may deem necessary in order to comply with the requirements of
Code Section 423. Decisions of the Plan Administrator shall be final and
binding on all parties having an interest in the Plan.

III.     STOCK SUBJECT TO PLAN

         A. The stock purchasable under the Plan shall be shares of authorized
but unissued or reacquired Common Stock, including shares of Common Stock
purchased on the open market. The maximum number of shares of Common Stock
which may be issued over the term of the Plan shall not exceed Five Hundred
Thousand (500,000) shares.

         B. 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 class of securities issuable under
the Plan, (ii) the maximum number and class of securities purchasable per
Participant on any one Purchase Date and (iii) the number and class of
securities and the price per share in effect under each outstanding purchase
right in order to prevent the dilution or enlargement of benefits thereunder.

IV.      OFFERING PERIODS

         A. Shares of Common Stock shall be offered for purchase under the Plan
through a series of successive offering periods until such time as (i) the
maximum number of shares of Common Stock available for issuance under the Plan
shall have been purchased or (ii) the Plan shall have been sooner terminated.

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         B. The initial offering period shall commence at the Effective Time
and terminate on the last business day in December 1997. All subsequent
offering periods shall coincide with each calendar year.

         C. Each offering period shall be comprised of a series of successive
quarterly Purchase Intervals. Purchase Intervals shall begin on the first
business day in January, April, July and October each year and terminate on the
last business day in the following March, June, August and December,
respectively. However, the first Purchase Interval under the initial offering
period shall commence at the Effective Time and terminate on the last business
day in December, 1996.

V.       ELIGIBILITY

         A. Each Eligible Employee shall be eligible to enter an offering
period under the Plan on the start date of any Purchase Interval within that
offering period, provided he or she remains an Eligible Employee on that date.
The date an individual enters an offering period shall be designated his or her
Entry Date for purposes of that offering period.

         B. To participate in the Plan for a particular offering period, the
Eligible Employee must complete the enrollment forms prescribed by the Plan
Administrator (including a stock purchase agreement and a payroll deduction
authorization form) and file such forms with the Plan Administrator (or its
designate) on or before his or her scheduled Entry Date.

VI.      PAYROLL DEDUCTIONS

         A. The payroll deduction authorized by the Participant for purposes of
acquiring shares of Common Stock during any offering period may be a fixed
dollar amount or any multiple of one percent (1%) of the Base Salary paid to
the Participant during each Purchase Interval within that offering period. In
all cases, the payroll deduction may not exceed a maximum of twenty percent
(20%) of Base Salary. The deduction rate so authorized shall continue in effect
throughout the offering period. The Participant may, prior to the beginning of
any Purchase Interval during the offering period, reduce or increase his or her
payroll deduction by filing the appropriate form with the Plan Administrator.
The new payroll deduction shall become effective as of the start date of the
first Purchase Interval following the filing of such form.

         B. Payroll deductions shall begin with the first pay day following the
Participant's Entry Date into the offering period and shall (unless sooner
terminated by the Participant) continue through the pay day ending with or
immediately prior to the last day of that offering period, provided that the
Plan Administrator may delay the first payroll deduction with respect to the
initial offering period. The amounts so collected shall be credited to the
Participant's book account under the Plan, but no interest shall be paid on the
balance from time to time outstanding in such account. The amounts collected
from the Participant shall not be held in any segregated account or trust fund
and may be commingled with the general assets of the Corporation and used for
general corporate purposes.

         C. Payroll deductions shall automatically cease upon the termination
of the Participant's purchase right in accordance with the provisions of the
Plan.

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         D. The Participant's acquisition of Common Stock under the Plan on any
Purchase Date shall neither limit nor require the Participant's acquisition of
Common Stock on any subsequent Purchase Date, whether within the same or a
different offering period.

VII.     PURCHASE RIGHTS

         A. Grant of Purchase Right. A Participant shall be granted a separate
purchase right for each Purchase Interval in which he or she participates in
each offering period in which he or she participates. The purchase right shall
be granted on the first business day of each Purchase Interval in which the
Participant participates and shall provide the Participant with the right to
purchase shares of Common Stock, upon the terms set forth below. The
Participant shall execute a stock purchase agreement embodying such terms and
conditions (not inconsistent with the Plan) as the Plan Administrator may deem
advisable.

Under no circumstances shall purchase rights be granted under the Plan to any
Eligible Employee if such individual would, immediately after the grant, own
(within the meaning of Code Section 424(d)) or hold outstanding options or
other rights to purchase, stock possessing five percent (5%) or more of the
total combined voting power or value of all classes of stock of the Corporation
or any Corporate Affiliate.

         B. Exercise of the Purchase Right. Each purchase right shall be
automatically exercised on the Purchase Date within the Purchase Interval, and
shares of Common Stock shall accordingly be purchased on behalf of each
Participant (other than any Participant whose payroll deductions have
previously been refunded in accordance with the Termination of Purchase Right
provisions below) on each such Purchase Date. The purchase shall be effected by
applying the Participant's payroll deductions for the Purchase Interval ending
on such Purchase Date to the purchase of shares of Common Stock (subject to the
limitation on the maximum number of shares purchasable per Participant on any
one Purchase Date) at the purchase price in effect for the Participant for that
Purchase Date.

         C. Purchase Price. The purchase price per share at which Common Stock
will be purchased on the Participant's behalf on each Purchase Date within the
offering period shall be equal to eighty-five percent (85%) of the lower of (i)
the Fair Market Value per share of Common Stock on the first business day of
each Purchase Interval or (ii) the Fair Market Value per share of Common Stock
on that Purchase Date.

         D. Excess Payroll Deductions. Any payroll deductions not applied to
the purchase of Common Stock by reason of the limitation on the maximum number
of shares purchasable by the Participant on the Purchase Date shall be
immediately refunded.

         E. Termination of Purchase Right. The following provisions shall
govern the termination of outstanding purchase rights:

                  (i) A Participant may, at any time prior to the next Purchase
Date in the offering period, terminate his or her outstanding purchase right by
filing the appropriate form with the Plan Administrator (or its designate), and
no further payroll deductions shall be collected from the Participant with
respect to the terminated purchase right. Any payroll

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deductions collected during the Purchase Interval in which such termination
occurs shall, at the Participant's election, be immediately refunded or held
for the purchase of shares on the next Purchase Date. If no such election is
made at the time such purchase right is terminated, then the payroll deductions
collected with respect to the terminated right shall be refunded as soon as
possible.

                  (ii) The termination of such purchase right shall be
irrevocable, and the Participant may not subsequently rejoin the offering
period for which the terminated purchase right was granted. In order to resume
participation in any subsequent offering period, such individual must re-enroll
in the Plan (by making a timely filing of the prescribed enrollment forms) on
or before his or her scheduled Entry Date into that offering period.

                  (iii) Should the Participant cease to remain an Eligible
Employee for any reason (including death, disability or change in status) while
his or her purchase right remains outstanding, then that purchase right shall
immediately terminate, and all of the Participant's payroll deductions for the
Purchase Interval in which the purchase right so terminates shall be
immediately refunded. However, should the Participant cease to remain in active
service by reason of an approved unpaid leave of absence, then the Participant
shall have the right, exercisable up until the last business day of the
Purchase Interval in which such leave commences, to (a) withdraw all the
payroll deductions collected during such Purchase Interval or (b) have such
funds held for the purchase of shares on the next scheduled Purchase Date. In
no event, however, shall any further payroll deductions be collected from the
Participant during such leave. Upon the Participant's return to active service,
his or her payroll deductions under the Plan shall automatically resume at the
rate in effect at the time the leave began.

         F. Corporate Transaction. Each outstanding purchase right shall
automatically be exercised, immediately prior to the effective date of any
Corporate Transaction, by applying the payroll deductions of each Participant
for the Purchase Interval in which such Corporate Transaction occurs to the
purchase of shares of Common Stock at a purchase price per share equal to
eighty-five percent (85%) of the lower of (i) the Fair Market Value per share
of Common Stock on the first business day of the Purchase Interval in which
such Corporate Transaction occurs or (ii) the Fair Market Value per share of
Common Stock immediately prior to the effective date of such Corporate
Transaction. However, the applicable limitation on the number of shares of
Common Stock purchasable per Participant on any one Purchase Date shall
continue to apply to any such purchase.

The Corporation shall use its best efforts to provide at least ten (10)-days
prior written notice of the occurrence of any Corporate Transaction, and
Participants shall, following the receipt of such notice, have the right to
terminate their outstanding purchase rights prior to the effective date of the
Corporate Transaction.

         G. Proration of Purchase Rights. Should the total number of shares of
Common Stock which are to be purchased pursuant to outstanding purchase rights
on any particular date exceed the number of shares then available for issuance
under the Plan, the Plan Administrator shall make a pro-rata allocation of the
available shares on a uniform and nondiscriminatory basis, and the payroll
deductions of each Participant, to the extent in excess of the aggregate
purchase price payable for the Common Stock pro-rated to such individual, shall
be refunded.


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         H. Assignability. The purchase right shall be exercisable only by the
Participant and shall not be assignable or transferable by the Participant.

         I. Stockholder Rights. A Participant shall have no stockholder rights
with respect to the shares subject to his or her outstanding purchase right
until the shares are purchased on the Participant's behalf in accordance with
the provisions of the Plan and the Participant has become a holder of record of
the purchased shares.

VIII.    ACCRUAL LIMITATIONS

         A. No Participant shall be entitled to accrue rights to acquire Common
Stock pursuant to any purchase right outstanding under this Plan if and to the
extent such accrual, when aggregated with (i) rights to purchase Common Stock
accrued under any other purchase right granted under this Plan and (ii) similar
rights accrued under other employee stock purchase plans (within the meaning of
Code Section 423) of the Corporation or any Corporate Affiliate, would
otherwise permit such Participant to purchase more than Twenty-Five Thousand
Dollars ($25,000) worth of stock of the Corporation or any Corporate Affiliate
(determined on the basis of the Fair Market Value of such stock on the date or
dates such rights are granted) for each calendar year such rights are at any
time outstanding.

         B. For purposes of applying such accrual limitations, the following
provisions shall be in effect:

                  (i) The right to acquire Common Stock under each outstanding
purchase right shall accrue in a series of installments on each successive
Purchase Date during the calendar year such rights are at any time outstanding.

                  (ii) No right to acquire Common Stock under any outstanding
purchase right shall accrue to the extent the Participant has already accrued
in the same calendar year the right to acquire Common Stock under one (1) or
more other purchase rights at a rate equal to Twenty-Five Thousand Dollars
($25,000) worth of Common Stock (determined on the basis of the Fair Market
Value per share on the date or dates of grant) for each calendar year such
rights were at any time outstanding.

         C. If by reason of such accrual limitations, any purchase right of a
Participant does not accrue for a particular Purchase Interval, then the
payroll deductions which the Participant made during that Purchase Interval
with respect to such purchase right shall be promptly refunded.

         D. In the event there is any conflict between the provisions of this
Article and one or more provisions of the Plan or any instrument issued
thereunder, the provisions of this Article shall be controlling.

IX.      EFFECTIVE DATE AND TERM OF THE PLAN

         A. The Plan was adopted by the Board on July 18, 1996 and shall become
effective at the Effective Time, provided no purchase rights granted under the
Plan shall be exercised, and no shares of Common Stock shall be issued
hereunder, until (i) the Plan shall have been


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approved by the stockholders of the Corporation and (ii) the Corporation shall
have complied with all applicable requirements of the 1933 Act (including the
registration of the shares of Common Stock issuable under the Plan on a Form
S-8 registration statement filed with the Securities and Exchange Commission),
all applicable listing requirements of any stock exchange (or the Nasdaq
National Market, if applicable) on which the Common Stock is listed for trading
and all other applicable requirements established by law or regulation. In the
event such stockholder approval is not obtained, or such compliance is not
effected, within twelve (12) months after the date on which the Plan is adopted
by the Board, the Plan shall terminate and have no further force or effect and
all sums collected from Participants during the initial offering period
hereunder shall be refunded.

         B. Unless sooner terminated by the Board, the Plan shall terminate
upon the earliest of (i) ten years from the date on which the plan was adopted,
(ii) the date on which all shares available for issuance under the Plan shall
have been sold pursuant to purchase rights exercised under the Plan or (iii)
the date on which all purchase rights are exercised in connection with a
Corporate Transaction. No further purchase rights shall be granted or
exercised, and no further payroll deductions shall be collected, under the Plan
following such termination.

X.       AMENDMENT OF THE PLAN

The Board may alter, amend, suspend or discontinue the Plan at any time to
become effective immediately following the close of any Purchase Interval,
provided that the Board may condition the effectiveness of any such amendment
on the Corporation having obtained the prior approval of the Corporation's
stockholders.

XI.      GENERAL PROVISIONS


         A. All costs and expenses incurred in the administration of the Plan
shall be paid by the Corporation.

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

         C. The provisions of the Plan shall be governed by the laws of the
State of California without resort to that State's conflict-of-laws rules.


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                                   SCHEDULE A


                         CORPORATIONS PARTICIPATING IN
                          EMPLOYEE STOCK PURCHASE PLAN
                            AS OF THE EFFECTIVE TIME

                      First Virtual Holdings Incorporated
                               MessageMedia, Inc.
                             Email Publishing Inc.
                            Distributed Bits L.L.C.
                              Revnet Systems, Inc.
                           Decisive Technology, Inc.


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                                    APPENDIX

The following definitions shall be in effect under the Plan:

         A. BASE SALARY shall mean the regular base salary paid to a
Participant by one or more Participating Companies during such individual's
period of participation in the Plan, plus any pre-tax contributions made by the
Participant to any Code Section 401(k) salary deferral plan or any Code Section
125 cafeteria benefit program now or hereafter established by the Corporation
or any Corporate Affiliate. The following items of compensation shall not be
included in Base Salary: (i) all overtime payments, bonuses, commissions (other
than those functioning as base salary equivalents), profit-sharing
distributions and other incentive-type payments and (ii) any and all
contributions (other than Code Section 401(k) or Code Section 125
contributions) made on the Participant's behalf by the Corporation or any
Corporate Affiliate under any employee benefit or welfare plan now or hereafter
established.

         B. BOARD shall mean the Corporation's Board of Directors.

         C. CODE shall mean the Internal Revenue Code of 1986, as amended.

         D. COMMON STOCK shall mean the Corporation's common stock.

         E. CORPORATE AFFILIATE shall mean any parent or subsidiary corporation
of the Corporation (as determined in accordance with Code Section 424), whether
now existing or subsequently established.

         F. CORPORATE TRANSACTION shall mean either of the following
stockholder-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 assets of the Corporation in complete liquidation or
dissolution of the Corporation.

         G. CORPORATION shall mean MessageMedia, Inc., a Delaware corporation,
and any corporate successor to all or substantially all of the assets or voting
stock of MessageMedia, Inc. which shall by appropriate action adopt the Plan.

         H. EFFECTIVE TIME shall mean the time at which the Underwriting
Agreement is executed and finally priced. Any Corporate Affiliate which becomes
a Participating Corporation after such Effective Time shall designate a
subsequent Effective Time with respect to its employee-Participants.

         I. ELIGIBLE EMPLOYEE shall mean any person who is employed by a
Participating Corporation on a basis under which he or she is regularly
expected to render more



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than twenty (20) hours of service per week for more than five (5) months per
calendar year for earnings considered wages under Code Section 3401(a).

         J. ENTRY DATE shall mean the date an Eligible Employee first commences
participation in the offering period in effect under the Plan. The earliest
Entry Date under the Plan shall be the Effective Time.

         K. 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 or
any successor system. 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) For purposes of the initial offering period which
begins at the Effective Time, the Fair Market Value shall be deemed to be equal
to the price per share at which the Common Stock is sold in the initial public
offering pursuant to the Underwriting Agreement.

         L. 1933 ACT shall mean the Securities Act of 1933, as amended.

         M. PARTICIPANT shall mean any Eligible Employee of a Participating
Corporation who is actively participating in the Plan.

         N. PARTICIPATING CORPORATION shall mean the Corporation and such
Corporate Affiliate or Affiliates as may be authorized from time to time by the
Board to extend the benefits of the Plan to their Eligible Employees. The
Participating Corporations in the Plan as of the Effective Time are listed in
attached Schedule A.

         O. PLAN shall mean the Corporation's Employee Stock Purchase Plan, as
set forth in this document.

         P. PLAN ADMINISTRATOR shall mean the Board of Directors of the
Corporation or any committee of two (2) or more Board members appointed by the
Board to administer the Plan.

         Q. PURCHASE DATE shall mean the last business day of each Purchase
Interval. The initial Purchase Date shall be the last business day in December,
1996.

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         R. PURCHASE INTERVAL shall mean each successive period within the
offering period at the end of which there shall be purchased shares of Common
Stock on behalf of each Participant.

         S. STOCK EXCHANGE shall mean either the American Stock Exchange or the
New York Stock Exchange.

         T. UNDERWRITING AGREEMENT shall mean the agreement between the
Corporation and the underwriter or underwriters managing the initial public
offering of the Common Stock.



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