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                                                                Exhibit 10.15.1




July 20, 1999

Mr. Michael A. Clark
8514 Fulton Court
Oriando,FL 32835

Dear Mike:

         In consideration of your further employment with the Company, we are
proposing the following Amendment to your Employment Offer letter dated
February 27, 1997.

         SEVERANCE PACKAGE:

         The Company will provide you With a severance package in the event you
are terminated without cause. Without cause shall mean for any reason other
than:

         1.       Illegal acts (other than minor traffic violations or
                  misdemeanors), including but not limited to theft or
                  embezzlement.

         2.       Violation of published written policies of the Company or
                  violation of any confidentiality or proprietary information
                  agreement with the Company.

         3.       Irresponsible unauthorized acts of a willful nature in the
                  performance of duties or repeated failure to follow the
                  reasonable directions of the Board of Directors or Officers,
                  of the Company.

         The severance package will provide you with up to six (6) months bass
salary, twenty-five percent (25%) of your annual bonus, and benefit continuance
from the time of your involuntary termination for a six (6) month period. If
you are employed within six (6) months of your termination from the Company,
your severance payments Will stop at the time of your new employment. You will
continue to vest your stock options during your severance period which may be
up to six (6) months. If your employment is terminated without cause because
of, or within one (1) year after, a sale of the Company, you Will receive six
(6) months compensation (base salary and bonus), plus six (6) months benefit
continuance.


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         NON-DISPARAGEMENT

         You agree that should your employment with the Company terminate for
any reason, you WILL not disparage the Company, which includes, but is not
limited to, making negative comments about the Company, its products, its
employees, Officers, or Board of Directors, or your employment with the
Company. In addition, should your employment with the Company terminate for any
reason, the Company agrees to not disparage you.

         NON-SOLICITATION:

         You agree that for six (6) months following the your employment with
the Company, whether the termination shall be voluntary or involuntary, with or
without cause, or for any other reason whatsoever, you shall not, directly or
indirectly or on behalf of yourself or any other person or entity: (a) attempt
to hire any other employee of the Company or otherwise encourage or attempt to
encourage any other employee of the Company to leave employment with the
Company; or (b) in any manner or at any time, solicit or encourage or discuss
with any person, firm, corporation, or any business entity who are Customer of
the Company and/or other employees of the Company to cease doing business with
the Company and/or other employees of the Company. In the event you breach any
term contained in this Section, you immediately waive any right or entitlement
to the Severance Benefits described in the Employment Severance Agreement and
will pay to the Company an amount equal to any portion of the Severance
Benefits paid to you prior to your breach, in addition to any damages the
Company may be able to recover.

         If you are in agreement With the terms of this Amendment, please sign
and date below.

                                       Sincerely,


                                       /s/ Brian J. Andrew
                                       ----------------------------------------
                                           Brian J. Andrew

I accept the terms of this amendment to my offer of employment.


  /s/ Michael A. Clark
-----------------------------------
Name: Michael A. Clark

           8/2/99
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Date




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