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                                                                    Exhibit 10.3



                                 MAIL.COM, INC.
                       SUPPLEMENTAL 2000 STOCK OPTION PLAN

1.     PURPOSE.

       The purpose of the Mail.com, Inc. Supplemental 2000 Stock Option Plan
(the "Plan") is to provide a means for Mail.com, Inc. (the "Company") to grant
non-qualified stock options to certain employees, officers, directors, or
consultants of the Company.

2.     DEFINITIONS.

       As used in the Plan, the following terms shall have the meanings set
forth below:

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

       (b)   "Code" shall mean the Internal Revenue Code of 1986, as amended
from time to time, and any regulations promulgated thereunder.

       (c)   "Committee" shall mean the committee described in Section 3.

       (d)   "Company" shall mean Mail.com, Inc., a Delaware corporation, and
any successor corporation.

       (e)   "Exchange Act" shall mean the Securities Exchange Act of 1934, as
amended.

       (f)   "Fair Market Value" means, as of any date, the value of Stock or
other property determined as follows:

             (i)   If the Stock is listed on any established stock exchange or a
       national market system, including without limitation the Nasdaq National
       Market or The Nasdaq SmallCap Market of The Nasdaq Stock Market, its Fair
       Market Value shall be the closing sales price for such stock (or the
       closing bid, if no sales were reported) as quoted on such exchange or
       system for the last market trading day prior to the time of
       determination, as reported in The Wall Street Journal or such other
       source as the Committee deems reliable;

             (ii)  If the Stock is 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 Stock on
       the last market trading day prior to the day of determination; or

             (iii) In the absence of an established market for the Stock, or if
       Fair Market Value is in reference to property other than Stock, the Fair
       Market Value thereof shall be determined in good faith by the Committee.

       (g)   "Grantee" shall mean an employee, officer, director or consultant
of Mail.com, Inc. to whom the Company has granted an Option under the terms of
the Plan.
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       (h)   "Nonemployee Director" shall mean a director of the Company who is
a "nonemployee director" within the meaning of Rule 16b-3.

       (i)   "Option" shall mean a non-qualified stock option granted under the
Plan that is not intended to meet the requirements of Section 422 of the Code.

       (j)   "Option Agreement" shall mean a written agreement between the
Company and a Grantee as described in Section 6.

       (k)   "Plan" shall mean this Mail.com, Inc. Supplemental 2000 Stock
Option Plan, as amended from time to time.

       (l)   "Rule 16b-3" shall mean Rule 16b-3 promulgated by the Securities
and Exchange Commission under the Securities Exchange Act of 1934, as amended,
or any successor rule or regulation.

       (m)   "Stock" shall mean shares of Class A Common Stock, $.01 par value,
of the Company or such other securities or property as may become subject to
Options pursuant to an adjustment made under Section 8.

       (n)   "Subsidiary" shall mean any corporation (other than the Company) in
an unbroken chain of corporations beginning with the Company if each of the
corporations other than the last corporation in the unbroken chain owns more
than 50% of the total combined voting power of all classes of stock in one of
the other corporations in such chain.

3.     ADMINISTRATION.

       (a)   The Plan shall be administered by a committee (the "Committee")
designated by the Board. The Committee shall consist of at least two directors
and may consist of the entire Board; provided, however, that if the Committee
consists of less than the entire Board, each member shall be a Nonemployee
Director.

       (b)   The Committee shall have plenary authority in its discretion,
subject only to the express provisions of the Plan:

             (i)   to select the Grantees, the number of shares of Stock subject
       to each Option and terms of the Option granted to each Grantee (including
       without limitation the period during which such Option can be exercised
       and any restrictions on exercise), provided that, in making its
       determination, the Committee shall consider the position and
       responsibilities of the individual, the nature and value to the Company
       of his or her services and accomplishments, the individual's present and
       potential contribution to the success of the Company and any other
       factors that the Committee may deem relevant.

             (ii)  to determine the dates of the Option grants;

             (iii) to prescribe the form of the Option Agreements;

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             (iv)  to adopt, amend and rescind rules and regulations for the
       administration of the Plan and for its own acts and proceedings;

             (v)   to decide all questions and settle all controversies and
       disputes of general applicability that may arise in connection with the
       Plan; and

             (vi)  to modify or amend any outstanding Option as provided in
       Section 7(h).

       All decisions, determinations and interpretations with respect to the
foregoing matters shall be made by the Committee and shall be final and binding
upon all persons.

       (c)   DELEGATION. The Committee may delegate authority to an officer of
the Company to grant Options to Grantees who are not subject to the short-swing
profit rules of Section 16 of the Exchange Act, at the discretion of such
appointed officer; provided, however, that the appointed officer shall have no
authority to grant Options in units greater than 80,000 without approval of the
Committee.

       (d)   EXCULPATION. No member of the Board or Committee shall be
personally liable for monetary damages for any action taken or any failure to
take any action in connection with the administration of the Plan or the
granting of Options under it unless such action or failure to take action
constitutes self-dealing, willful misconduct or recklessness; provided, however,
that the provisions of this subsection shall not apply to the responsibility or
liability of a director pursuant to any criminal statute or to the liability of
a director for the payment of taxes pursuant to local, state or federal law.

       (e)   INDEMNIFICATION. Each member of the Board or Committee shall be
entitled without further act on his part or her part to indemnity from the
Company to the fullest extent provided by applicable law and the Company's
Certificate of Incorporation or Bylaws in connection with or arising out of any
action, suit or proceeding with respect to the administration of the Plan or the
granting of Options under it in which he or she may be involved by reason of
being or having been a member of the Board or Committee at the time of the
action, suit or proceeding.

4.     EFFECTIVENESS AND TERMINATION OF THE PLAN.

       The Plan shall become effective as of May 18, 2000. Any Option
outstanding at the time of termination of the Plan shall remain in effect in
accordance with its terms and conditions and those of the Plan. The Plan shall
terminate on the earliest of:

       (a)   on May 18, 2010; or

       (b)   the date when all shares of Stock reserved for issuance under
Section 5 of the Plan shall have been acquired through exercise of Options
granted under the Plan; or

       (c)   such earlier date as the Board may determine.

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5.     THE STOCK.

       The aggregate number of shares of Stock issuable under the Plan shall be
two million (2,000,000) shares. The aggregate number of shares of Stock issuable
under the Plan may be set aside out of the authorized but unissued shares of
Stock not reserved for any other purpose, or out of shares of Stock held in or
acquired for the treasury of the Company.

6.     OPTION AGREEMENT.

       Each Grantee shall enter into an Option Agreement with the Company
setting forth the terms and conditions of the Option issued to the Grantee,
consistent with the Plan. The form of Option Agreement shall be established by
the Committee. No Grantee shall have rights in any Option unless and until an
Option Agreement is entered into with the Company.

7.     TERMS AND CONDITIONS OF OPTIONS.

       Options may be granted by the Committee at any time and from time to time
prior to the termination of the Plan. Except as hereinafter provided, Options
granted under the Plan shall be subject to the following terms and conditions:

       (a)   GRANTEES. The Grantees shall be those employees, officers,
directors, or consultants of the Company or its Subsidiaries selected by the
Committee.

       (b)   PRICE. The exercise price of an Option granted under the Plan shall
be the Fair Market Value of the Stock, without regard to any restriction, at the
time the Option is granted.

       (c)   PAYMENT FOR STOCK. The exercise price of an Option shall be paid in
full at the time of the exercise in (i) cash, or (ii) by certified check payable
to the Company, or (iii) by other mode of payment as the Committee may approve.

       (d)   DURATION AND EXERCISE OF OPTIONS. Options may be exercised for
terms of up to but not exceeding ten years from the date of grant. Subject to
the foregoing, Options shall be exercisable at the times and in the amounts (up
to the full amount thereof) determined by the Committee at the time of grant. If
an Option granted under the Plan is exercisable in installments, the Committee
shall determine what events, if any, will make it subject to acceleration.

       (e)   TERMINATION OF SERVICES. Upon the termination of a Grantee's
services for the Company or its Subsidiaries for any reason, Options held by the
Grantee may only be exercised to the extent and during the period, if any, set
forth in the Option Agreement.

       (f)   TRANSFERABILITY OF OPTION. No Option shall be transferable except
by will or the laws of descent and distribution. An Option shall be exercisable
during the Grantee's lifetime only by the Grantee.

       (g)   MODIFICATION, EXTENSION AND RENEWAL OF OPTIONS. Subject to the
terms and conditions and within the limitations of the Plan, the Committee may
modify, extend or renew outstanding Options granted under the Plan, or accept
the surrender of outstanding options (to








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the extent not theretofore exercised) and authorize the granting of new Options
in substitution thereof. Notwithstanding the foregoing, however, no
modification of an Option shall, without the consent of the Grantee, alter or
impair any rights or obligations under any Option theretofore granted under the
Plan.


       (h)   OTHER TERMS AND CONDITIONS. Option Agreements may contain any other
provision not inconsistent with the Plan that the Committee deems appropriate.

8.     ADJUSTMENT FOR CHANGES IN THE STOCK.

       (a)   In the event the shares of Stock, as presently constituted, shall
be changed into or exchanged for a different number or kind of shares or other
securities of the Company (whether by reason of merger, consolidation,
recapitalization, reclassification, split, reverse split, combination of shares
or otherwise), then there shall be substituted for or added to each share of
Stock theretofore or thereafter subject to an Option the number and kind of
shares of capital stock or other securities into which each outstanding share of
Stock shall be changed, or for which each such share shall be exchanged, or to
which each such share shall be entitled, as the case may be. The price and other
terms of outstanding Options shall also be appropriately amended to reflect the
foregoing events. In the event there shall be any other change in the number or
kind of outstanding shares of the Stock, or of any capital stock or other
securities into which the Stock shall have been changed or for which it shall
have been exchanged, if the Committee shall, in its sole discretion, determine
that the change equitably requires an adjustment in any Option theretofore
granted or which may be granted under the Plan, then adjustments shall be made
in accordance with its determination.

       (b)   Fractional shares resulting from any adjustment in Options pursuant
to this Section 8 may be settled in cash or otherwise as the Committee shall
determine. Notice of any adjustment shall be given by the Company to each holder
of an Option that shall have been so adjusted, and the adjustment (whether or
not notice is given) shall be effective and binding for all purposes of the
plan.

       (c)   Notwithstanding Section 8(a), the Committee shall have the power,
in the event of the disposition of all or substantially all of the assets of the
Company, or the dissolution of the Company, or the merger or consolidation of
the Company, or the making of a tender offer to purchase all or a substantial
portion of outstanding Stock of the Company, to amend all outstanding Options
(upon such conditions as it shall deem fit) to (i) permit the exercise of
Options prior to the effective date of the transaction and to terminate all
unexercised Options as of that date, or (ii) require the forfeiture of all
Options, provided the Company pays to each Grantee the excess of the Fair Market
Value of the Stock subject to the Option over the exercise price of the Option,
or (iii) make any other provisions that the Committee deems equitable.

9.     AMENDMENT OF THE PLAN.

       The Board may amend the Plan, may correct any defect or supply any
omission or reconcile any inconsistency in the Plan or in any Option in the
manner and to the extent deemed desirable to carry out the Plan without action
on the part of the stockholders of the Company.

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10.    INTERPRETATION AND CONSTRUCTION.

       The interpretation and construction of any provision of the Plan by the
Committee shall be final, binding and conclusive for all purposes.

11.    APPLICATION OF FUNDS.

       The proceeds received by the Company from the sale of Stock pursuant to
this Plan will be used for general corporate purposes.

12.    NO OBLIGATION TO EXERCISE OPTION.

       The granting of an Option shall impose no obligation upon the Grantee to
exercise an Option.

13.    PLAN NOT A CONTRACT OF EMPLOYMENT.

       Neither the Plan nor any Option Agreement is a contract of employment,
and the terms of employment of any Grantee shall not be affected in any way by
the Plan or related instruments except as specifically provided therein. The
establishment of the Plan shall not be construed as conferring any legal rights
upon any Grantee for a continuance of employment; nor shall it interfere with
the right of the Company (or its Subsidiary, if applicable) to discharge the
Grantee.

14.    EXPENSE OF THE PLAN.

       All of the expenses of administering the Plan shall be paid by the
Company.

15.    COMPLIANCE WITH APPLICABLE LAW.

       Notwithstanding anything herein to the contrary, the Company shall not be
obligated to cause to be issued or delivered any certificates for shares of
Stock issuable upon exercise of an Option unless and until the Company is
advised by its counsel that the issuance and delivery of the certificates is in
compliance with all applicable laws, regulations of government authorities and
the requirements of any exchange upon which shares of Stock are traded. The
Company shall in no event be obligated to register any securities pursuant to
the Securities Act of 1933 (as now in effect or as hereafter amended) or to take
any other action in order to cause the issuance and delivery of certificates to
comply with any of those laws, regulations or requirements. The Committee may
require, as a condition of the issuance and delivery of certificates and in
order to ensure compliance with those laws, regulations and requirements, that
the Grantee make such covenants, agreements and representations as the
Committee, in its sole discretion, deems necessary or desirable. Each Option
shall be subject to the further requirement that if at any time the Committee
shall determine in its discretion that the listing or qualification of the
shares of Stock subject to the Option, under any securities exchange
requirements or under any applicable law, or the consent or approval of any
regulatory body, is necessary in connection with the granting of the Option or
the issuance of Stock thereunder, the Option may not be exercised in whole or in
part unless the listing, qualification, consent or approval shall have been
effected or obtained free of any conditions not acceptable to the Committee.

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16.    GOVERNING LAW.

       Except to the extent preempted by federal law, this Plan shall be
construed and enforced in accordance with, and governed by, the laws of the
State of Delaware.


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