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                                                                   EXHIBIT 10.51

                              [MESSAGEMEDIA LOGO]


VIA FACSIMILE

September 30, 1999

Martin T. Johnson
1815 North Howe Street #F
Chicago, Illinois  60614


Dear Tork:

MessageMedia, Inc. ("MessageMedia" or the "Company") is pleased to offer you
employment on the terms and conditions stated in this letter, contingent upon
satisfactory reference checks. MessageMedia is offering you the position of Vice
President and Chief Financial Officer. You will work at our facility located at
6060 Spine Road, Boulder, Colorado 80301. You will report to Larry Jones,
President & CEO. Of course, MessageMedia may change your position, duties, and
work location from time to time as it deems necessary. Your employment shall
begin on the date on which you execute this Agreement.

Your rate of compensation will be $190,000 per year, less payroll deductions and
all required withholdings. MessageMedia agrees that your base salary will not be
reduced below $190,000 per year, unless the base salaries of other senior
executives are also subject to reductions. You will receive annual performance
reviews and annual consideration for salary increases. Your salary will be paid
in periodic installments in accordance with MessageMedia's customary practices
(as they may be changed by MessageMedia from time to time in its sole
discretion). At present, MessageMedia pays employees semi-monthly. You will be
eligible for all fringe benefits presently offered to senior executives. Details
about such benefits are available for your review.

In addition to your base salary, you will be eligible to earn an annual
performance bonus of up to 50% of your base salary, less applicable taxes, based
upon performance targets to be defined by the CEO. Bonuses, if any, will be paid
after the close of each fiscal year. The Company further agrees that you will
receive an annual performance bonus of $23,750 for the period through December
31, 1999, less applicable taxes and all required withholdings ("1999 Bonus"),
and an annual performance bonus of at least $47,500 for the period January 1,
2000 through December 31, 2000, less applicable taxes and all required
withholdings ("2000 Bonus").. You will not be eligible to receive the 1999 Bonus
if you voluntarily resign from the Company, or are terminated by the Company for
Cause, as defined below, on or before December 31, 1999. You will not be
eligible to receive the 2000 Bonus if you voluntarily resign from the Company,
or are terminated by the Company for Cause, on or before December 31, 2000. If
the company terminates your employment for a reason other than Cause (as defined
below) before December 31, 1999, you



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will be eligible to receive a pro rata share of the 1999 Bonus but no portion of
the 2000 Bonus. If the Company terminates your employment for a reason other
than Cause (as defined below) between January 1, 2000 and December 31, 2000, you
will be eligible to receive a pro rata share of the 2000 Bonus.

For your first eighteen (18) months of employment, the Company will also pay you
a monthly housing allowance of $4,000 per month and a travel allowance of
$1,300, less payroll deductions and all required withholdings. The travel
allowance covers personal, non-business related travel between Chicago and
Boulder for either yourself or your spouse. Any payments for a housing allowance
or travel allowance shall end on the earlier of eighteen months after execution
of this agreement or the date of termination of your employment, whether you
resign or are terminated with or without cause.

You will be entitled to four weeks of paid vacation during your first year of
service, which shall begin accruing monthly upon commencement of employment. You
will be entitled to use two weeks of paid vacation during your first six months
of service. Thereafter, vacation will be accrued in accordance with the
provisions of the MessageMedia Employee Handbook.

You are eligible to receive an option to purchase 300,000 shares of the
Company's Common Stock (the "Option"), with an exercise price per share equal to
the fair market value of the Company's Common Stock on the date on which you
begin your employment with MessageMedia ("Vesting Commencement Date"). To the
maximum extent possible, the Option shall be an incentive stock option as such
term is defined in Section 422 of the Internal Revenue Code of 1986, as amended.
To the extent that any portion of the Option does not qualify as incentive stock
options under Section 422 of the code, that the portion of the Option shall be
treated as a nonstatutory stock option. This option will be issued in accordance
with and subject to the terms and conditions of MessageMedia's 1995 Stock Option
Plan.

The Option shall vest in accordance with the Company's standard form of option
agreement under MessageMedia's 1995 Stock Option Plan, as amended, which, among
other terms, conditions, and limitations, provides that 25% of the shares
subject to the Option shall vest and become exercisable on the first anniversary
of the Vesting Commencement Date, and an additional 1/48th of the shares subject
to the option at the end of each one-month period thereafter shall vest and
become exercisable, during the period in which you remain an employee and/or
consultant of the Company.

Your employment is at-will and may be terminated at any time, with or without
notice, with or without cause, by either you or the Company. If the Company
terminates your employment without Cause, upon your furnishing to the Company
(1) an executed waiver and release form, releasing the Company from any claims
you may have against it, including a release of any and all claims under the
Federal Age discrimination in Employment Act of 1967, as amended, and (2) a
recognition of your continuing obligations under the Proprietary Information and
Inventions Agreement, attached hereto as Exhibit A, then the Company will pay
you an amount equal to twelve months of your then-current base salary, subject
to standard payroll deductions and required withholdings ("Severance Benefit").

For purposes of this Agreement, "Cause" for termination will mean: That
MessageMedia, acting in good faith based upon the information then known to
MessageMedia, determines that you have engaged in (embezzlement, fraud, theft,
misappropriation of corporate funds, or other acts of dishonesty; (2) serious
misconduct in the performance of your job duties which is materially



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harmful to MessageMedia (including but not limited to sexual or other forms of
harassment, and discrimination); (3) conduct which is likely to materially harm
or materially harms MessageMedia's reputation in the community; (4) refusal to
perform or substantially disregard of your assigned duties (including, but not
limited to, refusal to travel, refusal to work the requested hours, failure to
adequately perform job duties); (5) any material violation of any statutory,
contractual, or common law duty to MessageMedia (including but not limited to
fiduciary duties and the duty of loyalty), or (6) any material breach of any
term of this Agreement, including the Proprietary Information and Inventions
Agreement. In the event you are terminated for Cause, you will not be entitled
to any Severance Benefit, but you will be entitled to all compensation, benefits
and unreimbursed expenses (in accordance with MessageMedia's policy regarding
expense reimbursement ) accrued through the date of termination. This definition
of Cause is not intended and does not apply to any aspect of the relationship
between MessageMedia and you, beyond determining your eligibility for receiving
the Severance Benefit following termination by the Company. If you terminated
for Cause, you agree and acknowledge that you will continue to be bound by the
obligation set forth in Exhibit A, the Proprietary Information and Inventions
Agreement.

You also will be eligible to receive the Severance Benefit if you render your
resignation to MessageMedia, after notice to the Company, and within thirty days
after the occurrence of one of the following, if such events occur at the
Company's direction and without your consent: (1) you no longer report to the
person acting as Chief Executive Officer of MessageMedia; (2) your base salary
is decreased below $190,000 per year, unless the base salaries of other senior
executives are also subject to reductions; (3) your duties are materially and
permanently reduced, such that you no longer have the duties of a Chief
Financial Officer; (4) you no longer have the title "Chief Financial Officer";
or (5) you are required to relocate your primary residence out of the
metropolitan Chicago, Illinois area.

Mr. Johnson may not assign any rights or obligation arising under this
Agreement. MessageMedia may assign any right or obligation arising under this
Agreement. This Agreement shall bind the heirs, personal representatives,
successors, executors, and administrators of each party, and insure to the
benefit of each party, its heirs, and successors, MessageMedia shall take
appropriate steps to ensure that its obligations under this letter agreement are
binding on any successors and assigns of MessageMedia.

Should you accept this offer, your employment with MessageMedia will not be for
a specified term and may be terminated with or without cause and with or without
notice by you or by the Company at any time, for any reason or no reason. Any
contrary representations or agreements which may have been made to you are
superseded by this offer. The offer of employment described in this letter and
your acceptance of such terms shall constitute the entire Agreement between you
and MessageMedia concerning the nature and duration of your employment. The fact
that the rate of your salary is stated in units of years or months, that any
other payments (including housing allowance and travel allowance) are stated in
units of years or months and that your vacation accrues annually does not alter
the at-will nature of the employment, and does not mean and should not be
interpreted to mean that you are guaranteed employment to the end of any period
of time or for any period time. The "at will" term of your employment with
MessageMedia can only be changed in a Writing signed by you and the President of
the Company.



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One of the conditions of your employment with MessageMedia is the maintenance of
the confidentiality of MessageMedia's proprietary and confidential information.
You will be required, prior to or on your start date, to execute the Company's
Employee Proprietary Information and Inventions Agreement, attached hereto as
Exhibit A.

In your work for the Company, you will be expected not to use or disclose any
confidential information, including trade secrets, of any former employer or
other person to whom you have an obligation of confidentiality. You agree that
you will not bring onto Company premises any unpublished documents or property
belonging to any former employer or other person to whom you have an obligation
of confidentiality. In the performance of your duties for the Company, you will
be expected to use only that information which is generally known and used by
persons with training and experience comparable to your own, which is common
knowledge in the industry or otherwise legally in the public domain, or which is
otherwise provided or developed by the Company.

By joining MessageMedia, you are agreeing to abide by all laws and regulations,
all Company policies and procedures, to acknowledge in writing that you have
read and are bound by the Company's Employee Handbook, when a copy is provided
to you, and that you are bound by the terms and conditions of the Company's
Proprietary Information and Inventions Agreement. Violations of these policies
may lead to immediate termination of employment. As required by law, this offer
is subject to satisfactory proof of your right to work in the United States. Mr.
Johnson agrees to be responsible for the payment of any taxes due from him as a
result of any and all compensation provided MessageMedia, including but not
limited to, any taxes arising from compensation, housing and travel allowances,
benefits, incentive stock options, and nonstatutory stock options.

We are looking forward to having you join MessageMedia, Inc. If you wish to
accept this offer, please sign below and return the fully executed letter prior
to the expiration date of October 1, 1999. You should keep one copy of this
letter for your own records.

Very truly yours,

MESSAGEMEDIA, INC.


---------------------------------                ------------------------------
Susan L. Morse                                   Date
VP of Human Resources



Acceptance:


---------------------------------                ------------------------------
Martin T. Johnson                                Date


CC: Larry Jones



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                        EMPLOYEE PROPRIETARY INFORMATION
                            AND INVENTIONS AGREEMENT
                                    COLORADO


         This Employee Proprietary Information and Inventions Agreement
("Agreement") is made in consideration for my employment or continued employment
by MESSAGEMEDIA, INCORPORATED (the "Company"), and the compensation now and
hereafter paid to me. I hereby agree as follows:


1. NONDISCLOSURE.

1.1 RECOGNITION OF COMPANY'S RIGHTS; NONDISCLOSURE. At all times during my
employment and thereafter, I will hold in strictest confidence and will not
disclose, use, lecture upon or publish any of the Company's Proprietary
Information (defined below), except as such disclosure, use or publication may
be required in connection with my work for the Company, or unless an officer of
the Company expressly authorizes such in writing. I will obtain Company's
written approval before publishing or submitting for publication any material
(written, verbal, or otherwise) that relates to my work at Company and/or
incorporates any Proprietary Information. I hereby assign to the Company any
rights I may have or acquire in such Proprietary Information and recognize that
all Proprietary Information shall be the sole property of the Company and its
assigns.

1.2 PROPRIETARY INFORMATION. The term "PROPRIETARY INFORMATION" shall mean any
and all confidential and/or proprietary knowledge, data or information of the
Company. By way of illustration but not limitation, "Proprietary Information"
includes (a) trade secrets, inventions, mask works, ideas, processes, formulas,
source and object codes, data, programs, other works of authorship, know-how,
improvements, discoveries, developments, designs and techniques (hereinafter
collectively referred to as "Inventions"); and (b) information regarding plans
for research, development, new products, marketing and selling, business plans,
budgets and unpublished financial statements, licenses, prices and costs,
suppliers and customers; and (c) information regarding the skills and
compensation of other employees of the Company. Notwithstanding the foregoing,
it is understood that, at all such times, I am free to use information which is
generally known in the trade or industry, which is not gained as result of a
breach of this Agreement, and my own, skill, knowledge, know-how and experience
to whatever extent and in whichever way I wish.

1.3 THIRD PARTY INFORMATION. I understand, in addition, that the Company has
received and in the future will receive from third parties confidential or
proprietary information ("Third Party Information") subject to a duty on the
Company's part to maintain the confidentiality of such information and to use it
only for certain limited purposes. During the term of my employment and
thereafter, I will hold Third Party Information in the strictest confidence and
will not disclose to anyone (other than Company personnel who need to know such
information in connection with their work for the Company) or use, except in
connection with my work for the Company, Third Party Information unless
expressly authorized by an officer of the Company in writing.

1.4 NO IMPROPER USE OF INFORMATION OF PRIOR EMPLOYERS AND OTHERS. During my
employment by the Company I will not improperly use or disclose any confidential
information or trade secrets, if any, of any former employer or any other person
to whom I have an obligation of confidentiality, and I will not bring onto the
premises of the Company any unpublished documents or any property belonging to
any former employer or any other person to whom I have an obligation of
confidentiality unless consented to in writing by that former employer or
person. I will use in the performance of my duties only information which is
generally known and used by persons with training and experience comparable to
my own, which is common knowledge in the industry or otherwise legally in the
public domain, or which is otherwise provided or developed by the Company.

2. ASSIGNMENT OF INVENTIONS.

2.1 PROPRIETARY RIGHTS. The term "PROPRIETARY RIGHTS" Shall mean all trade
secret, patent, copyright, mask work and other intellectual property rights
throughout the world.

2.2 PRIOR INVENTIONS. Inventions, if any, patented or unpatented, which I made
prior to the commencement of my employment with the Company are excluded from
the scope of this Agreement. To



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preclude any possible uncertainty, I have set forth on Exhibit A (Previous
Inventions) attached hereto a complete list of all Inventions that I have, alone
or jointly with others, conceived, developed or reduced to practice or caused to
be conceived, developed or reduced to practice prior to the commencement of my
employment with the Company, that I consider to be my property or the property
of third parties and that I wish to have excluded from the scope of this
Agreement (collectively referred to as "Prior Inventions"). If disclosure of any
such Prior Invention would cause me to violate any prior confidentiality
agreement, I understand that I am not to list such Prior Inventions in Exhibit A
but am only to disclose a cursory name for each such invention, a listing of the
party(ies) to whom it belongs and the fact that full disclosure as to such
inventions has not been made for that reason. A space is provided on Exhibit A
for such purpose. If no such disclosure is attached, I represent that there are
no Prior Inventions. If, in the course of my employment with the Company, I
incorporate a Prior Invention into a Company product, process or machine, the
Company is hereby granted and shall have a nonexclusive, royalty-free,
irrevocable, perpetual, worldwide license (with rights to sublicense through
multiple tiers of sublicensees) to make, have made, modify, use and sell such
Prior Invention. Notwithstanding the foregoing, I agree that I will not
incorporate, or permit to be incorporated, Prior Inventions in any Company
Inventions without the Company's prior written consent.

2.3 ASSIGNMENT OF INVENTIONS. Subject to Sections 2.4, and 2.6, I hereby assign
and agree to assign in the future (when any such Inventions or Proprietary
Rights are first reduced to practice or first fixed in a tangible medium, as
applicable) to the Company all my right, title and interest in and to any and
all Inventions (and all Proprietary Rights with respect thereto) whether or not
patentable or registrable under copyright or similar statutes, made or conceived
or reduced to practice or learned by me, either alone or jointly with others,
during the period of my employment with the Company. Inventions assigned to the
Company, or to a third party as directed by the Company pursuant to this Section
2, are hereinafter referred to as "Company Inventions."

2.4 NONASSIGNABLE INVENTIONS. I recognize that, in the event of a specifically
applicable state law, regulation, rule, or public policy ("Specific Inventions
Law"), this Agreement will not be deemed to require assignment of any invention
which qualifies fully for protection under a Specific Inventions Law by virtue
of the fact that any such invention was, for example, developed entirely on my
own time without using the Company's equipment, supplies, facilities, or trade
secrets and neither related to the Company's actual or anticipated business,
research or development, nor resulted from work performed by me for the Company.
In the absence of a Specific Inventions Law, the preceding sentence will not
apply.

2.5 OBLIGATION TO KEEP COMPANY INFORMED. During the period of my employment and
for six months after the last day of my employment with the Company, I will
promptly disclose to the Company fully and in writing all Inventions authored,
conceived or reduced to practice by me, either alone or jointly with others. In
addition, I will promptly disclose to the Company all patent applications filed
by me or on my behalf within a year after termination of employment. At the time
of each such disclosure, I will advise the Company in writing of any Inventions
that I believe fully qualify for protection under the provisions of a Specific
Inventions Law; and I will at that time provide to the Company in writing all
evidence necessary to substantiate that belief. The Company will keep in
confidence and will not use for any purpose or disclose to third parties without
my consent any confidential information disclosed in writing to the Company
pursuant to this Agreement relating to Inventions that qualify fully for
protection under a Specific Inventions Law. I will preserve the confidentiality
of any Invention that does not fully qualify for protection under a Specific
Inventions Law.

2.6 GOVERNMENT OR THIRD PARTY. I also agree to assign all my right, title and
interest in and to any particular Invention to a third party, including without
limitation the United States, as directed by the Company.

2.7 WORKS FOR HIRE. I acknowledge that all original works of authorship which
are made by me (solely or jointly with others) within the scope of my employment
and which are protectable by copyright are "works made for hire," pursuant to
United States Copyright Act (17 U.S.C., Section 101).

2.8 ENFORCEMENT OF PROPRIETARY RIGHTS. I will assist the Company in every proper
way to obtain, and from time to time enforce, United States and foreign
Proprietary Rights relating to Company Inventions in any and all countries. To
that end I will execute, verify and deliver such documents and perform such
other acts (including appearances as a

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witness) as the Company may reasonably request for use in applying for,
obtaining, perfecting, evidencing, sustaining and enforcing such Proprietary
Rights and the assignment thereof. In addition, I will execute, verify and
deliver assignments of such Proprietary Rights to the Company or its designee.
My obligation to assist the Company with respect to Proprietary Rights relating
to such Company Inventions in any and all countries shall continue beyond the
termination of my employment, but the Company shall compensate me at a
reasonable rate after my termination for the time actually spent by me at the
Company's request on such assistance.

In the event the Company is unable for any reason, after reasonable effort, to
secure my signature on any document needed in connection with the actions
specified in the preceding paragraph, I hereby irrevocably designate and appoint
the Company and its duly authorized officers and agents as my agent and attorney
in fact, which appointment is coupled with an interest, to act for and in my
behalf to execute, verify and file any such documents and to do all other
lawfully permitted acts to further the purposes of the preceding paragraph with
the same legal force and effect as if executed by me. I hereby waive and
quitclaim to the Company any and all claims, of any nature whatsoever, which I
now or may hereafter have for infringement of any Proprietary Rights assigned
hereunder to the Company.

3. NO CONFLICTS OR SOLICITATION. I acknowledge that during my employment I will
have access to and knowledge of Proprietary Information. To protect the
Company's Proprietary Information, I agree that during the period of my
employment by the Company I will not, without the Company's express written
consent, engage in any other employment or business activity directly related to
the business in which the Company is now involved or becomes involved, nor will
I engage in any other activities which conflict with my obligations to the
Company. For the period of my employment by the Company and continuing until
twelve months after my last day of employment with the Company, I will not (a)
directly or indirectly induce any employee of the Company to terminate or
negatively alter his or her relationship with the Company or (b) solicit the
business of any client or customer of the Company (other than on behalf of the
Company) or (c) induce any supplier, vendor, consultant or independent
contractor of the Company to terminate or negatively alter his, her or its
relationship with the Company. If any restriction set forth in this Section is
found by any court of competent jurisdiction to be unenforceable because it
extends for too long a period of time or over too great a range of activities or
in too broad a geographic area, it shall be interpreted to extend only over the
maximum period of time, range of activities or geographic area as to which it
may be enforceable.

4. COVENANT NOT TO COMPETE. I acknowledge that during my employment I will have
access to and knowledge of Proprietary Information. To protect the Company's
Proprietary Information, I agree that during my employment with the Company
whether full-time or half-time and for a period of twelve months after my last
day of employment with the Company, I will not directly or indirectly engage in
(whether as an employee, consultant, proprietor, partner, director or
otherwise), or have any ownership interest in, or participate in the financing,
operation, management or control of, any person, firm, corporation or business
that engages in a "Restricted Business" in a "Restricted Territory" (as defined
below). It is agreed that ownership of (i) no more than one percent (1%) of the
outstanding voting stock of a publicly traded corporation, or (ii) any stock I
presently own shall not constitute a violation of this provision.

4.1 REASONABLE. I agree and acknowledge that the time limitation on the
restrictions in this paragraph, combined with the geographic scope, is
reasonable. I also acknowledge and agree that this paragraph is reasonably
necessary for the protection of Company's Proprietary Information as defined in
paragraph 1.2 herein, that through my employment I shall receive adequate
consideration for any loss of opportunity associated with the provisions herein,
and that these provisions provide a reasonable way of protecting Company's
business value which will be imparted to me. If any restriction set forth in
this paragraph 4 is found by any court of competent jurisdiction to be
unenforceable because it extends for too long a period of time or over too great
a range of activities or in too broad a geographic area, it shall be interpreted
to extend only over the maximum period of time, range of activities or
geographic area as to which it may be enforceable.

4.2 As used herein, the terms:

         (i) "Restricted Business" shall mean the design, development, marketing
or sales of e-mail based customer relationship management and direct marketing
services or any computer program, product, process, system or service marketed,
sold or under development by the Company at any time

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<PAGE>   8

during my employment with the Company. "Restricted Business" does not include
consulting businesses which design and develop customer relationship management
systems which include e-mail as one of many channels through which customers
communicate.

         (ii) "Restricted Territory" shall mean the countries and territories in
which the Company conducts business, and counties, cities, territories and
states of the United States.

5. RECORDS. I agree to keep and maintain adequate and current records (in the
form of notes, sketches, drawings and in any other form that may be required by
the Company) of all Proprietary Information developed by me and all Inventions
made by me during the period of my employment at the Company, which records
shall be available to and remain the sole property of the Company at all times.

6. ADDITIONAL ACTIVITIES. I agree that during the period of my employment by the
Company I will not, without the Company's express written consent, engage in any
employment or business activity which is competitive with, or would otherwise
conflict with, my employment by the Company.

7. NO CONFLICTING OBLIGATION. I represent that my performance of all the terms
of this Agreement and as an employee of the Company does not and will not breach
any agreement to keep in confidence information acquired by me in confidence or
in trust prior to my employment by the Company. I have not entered into, and I
agree I will not enter into, any agreement either written or oral in conflict
herewith.

8. RETURN OF COMPANY MATERIALS. When I leave the employ of the Company, I will
deliver to the Company any and all drawings, notes, memoranda, specifications,
devices, formulas, and documents, together with all copies thereof, and any
other material containing or disclosing any Company Inventions, Third Party
Information or Proprietary Information of the Company. I further agree that any
property situated on the Company's premises and owned by the Company, including
disks and other storage media, filing cabinets or other work areas, is subject
to inspection by Company personnel at any time with or without notice.

9. LEGAL AND EQUITABLE REMEDIES. Because my services are personal and unique and
because I may have access to and become acquainted with the Proprietary
Information of the Company, the Company shall have the right to enforce this
Agreement and any of its provisions by injunction, specific performance or other
equitable relief, without bond and without prejudice to any other rights and
remedies that the Company may have for a breach of this Agreement.

10. NOTICES. Any notices required or permitted hereunder shall be given to the
appropriate party at the address specified below or at such other address as the
party shall specify in writing. Such notice shall be deemed given upon personal
delivery to the appropriate address or if sent by certified or registered mail,
three days after the date of mailing.

11. NOTIFICATION OF NEW EMPLOYER. In the event that I leave the employ of the
Company, I hereby consent to the notification of my new employer of my rights
and obligations under this Agreement.

12. GENERAL PROVISIONS.

12.1 GOVERNING LAW; CONSENT TO PERSONAL JURISDICTION AND EXCLUSIVE FORUM. This
Agreement will be governed by and construed according to the laws of the State
of Colorado as such laws are applied to agreements entered into and to be
performed entirely within Colorado between Colorado residents. I hereby
expressly understand and consent that my employment is a transaction of business
in the State of Colorado and constitutes the minimum contacts necessary to make
me subject to the personal jurisdiction of the federal courts located in the
State of Colorado, and the state courts located in the County of Boulder,
Colorado, for any lawsuit filed against me by Company arising from or related to
this Agreement. I agree and acknowledge that any controversy arising out of or
relating to this Agreement or the breach thereof, or any claim or action to
enforce this Agreement or portion thereof, or any controversy or claim requiring
interpretation of this Agreement must be brought in a forum located within the
State of Colorado. No such action may be brought in any forum outside the State
of Colorado. Any action brought in contravention of this paragraph by one party
is subject to dismissal at any time and at any stage of the proceedings by the
other, and no action taken by the other in defending, counter claiming or
appealing shall be construed as a waiver of this right to immediate dismissal. A
party bringing

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<PAGE>   9


an action in contravention of this paragraph shall be liable to the other party
for the costs, expenses and attorney's fees incurred in successfully dismissing
the action or successfully transferring the action to the federal courts located
in the State of Colorado, or the state courts located in the County of Boulder,
Colorado.

12.2 SEVERABILITY. In case any one or more of the provisions contained in this
Agreement shall, for any reason, be held to be invalid, illegal or unenforceable
in any respect, such invalidity, illegality or unenforceability shall not affect
the other provisions of this Agreement, and this Agreement shall be construed as
if such invalid, illegal or unenforceable provision had never been contained
herein. If moreover, any one or more of the provisions contained in this
Agreement shall for any reason be held to be excessively broad as to duration,
geographical scope, activity or subject, it shall be construed by limiting and
reducing it, so as to be enforceable to the extent compatible with the
applicable law as it shall then appear.

12.3 SUCCESSORS AND ASSIGNS. This Agreement will be binding upon my heirs,
executors, administrators and other legal representatives and will be for the
benefit of the Company, its successors, and its assigns.

12.4 SURVIVAL. The provisions of this Agreement shall survive the termination of
my employment and the assignment of this Agreement by the Company to any
successor in interest or other assignee.

12.5 EMPLOYMENT. I agree and understand that my employment is at-will which
means I or the company each have the right to terminate my employment at will,
with or without advanced notice and with or without cause. I further agree and
understand that nothing in this Agreement shall confer any right with respect to
continuation of employment by the Company, nor shall it interfere in any way
with my right or the Company's right to terminate my employment at any time,
with or without cause.

12.6 WAIVER. No waiver by the Company of any breach of this Agreement shall be a
waiver of any preceding or succeeding breach. No waiver by the Company of any
right under this Agreement shall be construed as a waiver of any other right.
The Company shall not be required to give notice to enforce strict adherence to
all terms of this Agreement.

12.7 ENTIRE AGREEMENT. The obligations pursuant to Sections 1 through 4 and
Sections 6 and 7 (including all subparts) of this Agreement shall apply to any
time during which I was previously employed, or am in the future employed, by
the Company as a consultant if no other agreement governs nondisclosure and
assignment of inventions during such period. This Agreement is the final,
complete and exclusive agreement of the parties with respect to the subject
matter hereof and supersedes and merges all prior discussions between us. No
modification of or amendment to this Agreement, nor any waiver of any rights
under this Agreement, will be effective unless in writing and signed by the
party to be charged. Any subsequent change or changes in my duties, salary or
compensation will not affect the validity or scope of this Agreement

         This Agreement shall be effective as of the first day of my employment
with the Company, namely: _______________, 1999.

         I HAVE READ THIS AGREEMENT CAREFULLY AND UNDERSTAND ITS TERMS. I HAVE
COMPLETELY FILLED OUT EXHIBIT A TO THIS AGREEMENT.


Dated:
       ----------------------


-----------------------------
Signature


-----------------------------
Printed Name


ACCEPTED AND AGREED TO:


-----------------------------

                                       5

<PAGE>   10

                                    EXHIBIT A


TO:      MESSAGEMEDIA, INCORPORATED

FROM:
         -------------------

DATE:
         -------------------

SUBJECT: PREVIOUS INVENTIONS

         1. Except as listed in Section 2 below, the following is a complete
list of all inventions or improvements relevant to the subject matter of my
employment by MESSAGEMEDIA, INCORPORATED that have been made or conceived or
first reduced to practice by me alone or jointly with others prior to my
engagement by the Company:

         [ ]      No inventions or improvements.

         [ ]      See below:

                  --------------------------------------------------------------

                  --------------------------------------------------------------

                  --------------------------------------------------------------

         [ ]      Additional sheets attached.


         2. Due to a prior confidentiality agreement, I cannot complete the
disclosure under Section 1 above with respect to inventions or improvements
generally listed below, the proprietary rights and duty of confidentiality with
respect to which I woe to the following party(ies):

<TABLE>
<CAPTION>
      INVENTION OR IMPROVEMENT          PARTY(IES)            RELATIONSHIP
<S>                                <C>                    <C>
1.
      -----------------------      -------------------     -------------------
2.
      -----------------------      -------------------     -------------------
3.
      -----------------------      -------------------     -------------------
</TABLE>

         [ ]      Additional sheets attached.


                                      A-1