Document:

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                                                                Exhibit 10.15(a)

February 22, 2002

Mr. Bill Zierolf
President and CEO
CentrPort, Inc.
450 Post Road East
Westport, CT 06880

Re:   Amendment to the Reseller Agreement dated December 22, 2000 between
      Modem Media, Inc. and CentrPort, LLC (the "Reseller Agreement")

Dear Bill:

This letter confirms our agreement to amend the Reseller Agreement as follows:

1.   CentrPort agrees that Modem has no obligation to pay the Unpaid Amount to
     CentrPort and CentrPort waives any and all of its rights that it may have
     to receive the Unpaid Amount.

2.   The term "Revenue" shall include (i) all Revenue recognized by Vendor in
     connection with Vendor's arrangements with Interpublic Group of Companies,
     Inc. ("IPG") or any of IPG's affiliates; and (ii) license fees.

3.   Sections 3(h)(i) and 3(h)(ii) shall be deleted in their entirety and the
     following shall be substituted therefore:

     i.   During 2002, if Vendor recognizes Warrant Revenue equal to $7.5
          million, Vendor will issue Reseller warrants to purchase 587,406
          shares of common stock of Vendor. Vendor will issue Reseller
          additional warrants to purchase 391,604 shares of common stock for
          every incremental $2.5 million of Warrant Revenue achieved above $7.5
          million during 2002. All warrants issued pursuant to Section 3(h)(ii)
          shall be at an exercise price of $.90.

     ii.  During 2003, if Vendor recognizes Warrant Revenue equal to $10
          million, Vendor will issue Reseller warrants to purchase 587,406
          shares of common stock of Vendor. Vendor will issue Reseller
          additional warrants to purchase 391,604 shares of common stock for
          every incremental $2.5 million of Warrant Revenue achieved above $10
          million during 2003. All warrants issued pursuant to Section 3(h)(iii)
          shall be at an exercise price of $.90.

4.   Except as set forth in this letter, all other terms and conditions of the
     Reseller Agreement shall remain in full force and effect.

5.   All capitalized terms shall have their respective meanings as set forth in
     the Reseller Agreement.

Sincerely,

/s/ Marc Particelli
Marc Particelli
President and CEO

AGREED AND ACCEPTED THIS 22nd DAY OF FEBRUARY, 2002 BUT EFFECTIVE AS OF
DECEMBER 22, 2001

CENTRPORT, INC.

      Bill Zierolf                                By: /s/ Bill Zierolf
Date: February 22, 2002<PAGE>
                                                                   EXHIBIT 10(M)

          2001 Management Incentive Plan (MIP) Description Performance
                    Cycle January 1 through December 31, 2001

Introduction

The Management Incentive Plan (the "MIP" or the "Plan") is an annual incentive
plan for officers and other designated management associates where awards are
based on achievement of actual performance goals in relation to pre-determined
performance goal levels.

Eligibility and Participation

All officers and other designated management associates are eligible for
participation in the MIP. Individuals selected to participate (the
"Participant") will be notified in writing by the CEO or appropriate senior
staff member.

Target Award Opportunity

At the beginning of each Plan year, a target incentive level will be established
for each Participant. Target incentive levels will be expressed as a percentage
of base salary earned plus sales incentive target, if applicable. The
Participant earns the right to receive the target incentive award or a greater
or lesser award based on corporate and/or unit performance achievement levels.
Participants must maintain an acceptable level of individual performance during
the Plan year to receive an award. A Participant's incentive award shall be
based on his/her earned salary, exclusive of any bonus or fringe benefits.

Performance Goals

At the beginning of each Plan year, the CEO will establish performance goals
based on Participant's field and/or corporate staff responsibilities. The goals
will not be modified, once established for the Plan year, unless unforeseen
circumstances occur which would have substantially influenced the setting of the
goals had such circumstances been known at the time. Any such change is subject
to the approval of the Board.

Performance levels shall be established in the following areas:

1. Earnings - which encourages top performance at the corporate and unit levels

2. Membership - which ties associates to the growth of the company

3. Quality - which encourages each associate to focus on what's important to our
customers. Some participants may not have quality measures.

The weightings of these factors may be different between Participants depending
on his or her position and responsibilities.

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Form and Timing of Payment

MIP incentive awards will be paid via check by March 15 of the year following
the Plan year and after award amounts are approved by the Board.

New Hires, Promotions or Position Changes

Awards will be made on a pro-rated basis to those individuals who become
eligible (new hires or promotions) for participation during the course of the
Plan year. Associates hired on or after November 1 will not receive a prorated
award for the January 1 to December 31 performance cycle.

Any transfer or change in position of a Plan Participant during the Plan year,
resulting in participation at a lower target award level, will be recognized.
The Participant will receive an incentive award that is calculated based on the
pro-rated target award levels that were established for the Participant during
the Plan year. For example, if a Participant was in a MIP eligible position for
half of the Plan year at a 30% incentive target and then was promoted to another
eligible position at a 40% target, he or she would receive an award based on 30%
of their earned base salary during the first half of the year, plus 40% of base
salary earned during the balance of the year. If the transfer or change in
position results in non-eligibility for the Plan, a pro-rated award will be
calculated based on the Participant's actual period of active participation in
the Plan.

A Participant must have been in a MIP-eligible position for a minimum of two
months for any pro-rated award to be paid.

Termination - Death, Disability, or Retirement

If a Participant's employment is terminated due to death, disability, or
retirement during a Plan year, the award earned will be pro-rated based on the
number of days of participation during the Plan year. The Participant must have
been in the Plan a minimum of two months of the Plan year before an award is
paid. The award will be calculated based on the Participant's earned salary
during the time of active participation in the Plan.

Leave of Absence

A Participant who is granted a leave of absence during the Plan year is not
eligible to participate in the Plan during the time they are on leave from the
Company. However, at the discretion of the CEO, a Participant may be eligible to
receive partial incentive compensation for the period of time he or she was an
active participant in the Plan. No partial payments will be made if the period
of active participation was less than two months during the Plan year.

Other Termination

If a Participant's employment is terminated prior to December 31 of the Plan
year, whether voluntarily or involuntarily, for any other reason not specified
in this Plan, all unpaid awards under MIP will be forfeited.

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Tax Withholding

Cash payments are taxable to participants in the year of receipt based on the
federal, state and local tax law. Effect on Employee Benefit Plans

Payments from the MIP will be included in calculating the amount of associate
benefits to be paid under the terms of any of the Company's qualified associate
benefit plans, subject to the maximum allowable compensation established by
federal law. Deductions for 401(k) withholding for the Humana Inc. Retirement &
Savings Plan will occur based on the participant's withholding rate at the time
of payment.

Participant Rights

Participation in the MIP shall not create a contract of employment and shall not
interfere with the Company's right to terminate any participant's employment at
any time. Rights or interests of any Participant in the MIP are non-
transferable.

Plan Administration

The Senior Vice President of Human Resources of Humana Inc. will have
responsibility for administration of the MIP in accordance with the provisions
of this Plan.

Plan Amendments

The Board may, at its sole discretion, modify, amend, suspend or terminate, in
whole or in part, any or all of the provisions of the MIP.

Individual Performance

Participants must maintain an acceptable level of performance during the Plan
year in order to receive payment of their award. If a Participant's performance
is deficient, their earned award may be decreased or forfeited as needed at the
discretion of the Senior Vice President of Human Resources and the CEO.

               Management Incentive Plan Design
                  Corporate Staff Personnel

1. Corporate Earnings Measure - Corporate staff will be measured primarily on a
corporate earnings per share goal as follows:

                    Earnings Threshold          Earnings Target

  % of MIP         50% of the weighting      100% of the weighting
opportunity           for this factor           for this factor

If earnings threshold is achieved, the participant can also earn the amount
described in factor 2 below. For superior earnings achievement (over 100% target
level), the sum of factors 1 and 2 will then be multiplied by factor 3, the
corporate earnings modifier, as described below.

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2. Membership Target - Associates will be measured on corporate membership
(weighted ending membership with specialty products). Subject to hitting the
earnings threshold, the following will be added:

                  Membership Threshold         Membership Target

  % of MIP       50% of the weighting        100% of the weighting
opportunity        for this factor              for this factor

3. Corporate Earnings Modifier - To encourage the achievement of corporate
earnings above target, the following will be multiplied by the sum of factors 1
and 2. The maximum corporate earnings multiplier is 120%.

If corporate earnings are less than 100%, this factor does not apply.

         Corporate Earnings/Target         Multiplier
                   100%                      100%
              Maximum or above               120%

Note: All achievements between performance levels will be interpolated.

The company has the right to modify or terminate the Management Incentive Plan
if circumstances warrant. A MIP Plan Description is available from your Human
Resources Director.

                        Management Incentive Plan Design
                       Field and Corporate Line Personnel

1. Earnings Measure - Each Associate will have earnings targets (pre-tax
profits) for their primary unit, defined as a market, a region, territory,
company or other P & L unit. Each goal will have a threshold and a target that
would work as follows:

                  Earnings Threshold          Earnings Target

  % of MIP       50% of the weighting      100% of the weighting
opportunity         for this factor           for this factor

If earnings threshold is achieved, the participant can also earn the amount
described in factor 2 below. For superior unit earnings achievement (over 100%
target level), the sum of factors 1 and 2 will then be multiplied by factor 3 as
described below. Finally, that product will be multiplied by factor 4, the
corporate earnings modifier.

2. Membership Target - Associates will be measured on membership (weighted
ending membership with specialty products). Subject to hitting the earnings
threshold, the following will be added:

                  Membership Threshold         Membership Target

  % of MIP       50% of the weighting        100% of the weighting

                                                                          Page 4

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opportunity      for this factor          for this factor

3. Superior Unit Earnings Modifier - To encourage the achievement of unit
earnings above target, the following will be multiplied by the sum of factors 1
and 2. The maximum unit earnings multiplier is 120%. If unit earnings are less
than 100%, this factor does not apply.

        Unit Earnings/Target              Multiplier
                 100%                        100%
           Maximum or above                  120%

4. Corporate Earnings Modifier -The incentive earned through factor 3 will be
modified, with a maximum multiplier of 120%, as follows:

         Corporate Earnings/Target         Multiplier
            Threshold or less                 80%
                   100%                      100%
              Maximum or above               120%

Note: All achievements between performance levels will be interpolated.

The company has the right to modify or terminate the Management Incentive Plan
if circumstances warrant. A MIP Plan Description is available from your Human
Resources Director.

                        Management Incentive Plan Design
              Field and Corporate Line Personnel with Quality Goals

1. Earnings Measure - Each Associate will have earnings targets (pre-tax
profits) for their primary unit, defined as a market, a region, territory,
company or other P & L unit. Each goal will have a threshold and a target that
would work as follows:

                Earnings Threshold        Earnings Target

  % of MIP     50% of the weighting    100% of the weighting
opportunity       for this factor         for this factor

If earnings threshold is achieved, the participant can also earn the amounts
described in factors 2 and 3. For superior unit earnings achievement (over 100%
target level), the sum of factors 1, 2 and 3 will then be multiplied by factor 4
as described below. Finally, that product will be multiplied by factor 5, the
corporate earnings modifier.

2. Membership Target - Associates will be measured on membership (weighted
ending membership with specialty products). Subject to hitting the earnings
threshold, the following will be added:

              Membership Threshold      Membership Target

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        % of MIP        50% of the weighting         100% of the weighting
       opportunity         for this factor              for this factor

3. Quality Target - Applicable participants will have a quality, service or key
strategic/tactical objectives measure. Subject to hitting the earnings
threshold, the following will be added:

                Minimum Standards    Target Quality % of MIP

        % of MIP        50% of the weighting         100% of the weighting
       opportunity         for this factor              for this factor

4. Superior Unit Earnings Modifier - To encourage the achievement of unit
earnings above target, the following will be multiplied by the sum of factors 1,
2 and 3. The maximum unit earnings multiplier is 120%.

If unit earnings are less than 100%, this factor does not apply.

            Unit Earnings/Target           Multiplier
                    100%                      100%
              Maximum or above                120%

5. Corporate Earnings Modifier - The incentive earned through factor 4 will be
modified, with a maximum multiplier of 120%, as follows:

         Corporate Earnings/Target        Multiplier
            Threshold or less                 80%
                   100%                      100%
              Maximum or above               120%

Note: All achievements between performance levels will be interpolated.

The company has the right to modify or terminate the Management Incentive Plan
if circumstances warrant. A MIP Plan Description is available from your Human
Resources Director.

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