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                                                                   Exhibit 10.24

                                    March 31, 1999

Kathleen C. Little
50 Hosmer Street
Acton, MA  01720

Dear Kathleen:

      The purpose of this letter agreement is to set forth our mutual
understanding and agreement with respect to: (i) your separation from the
Company; and (ii) the establishment of the terms of your severance and
separation from employment. We have agreed as follows:

1.        Separation from Employment. Effective as of the close of business on
          Friday, May 7, 1999 (your "separation date"), you will no longer be a
          full-time employee of the Company, as the Company will terminate your
          employment without cause, and you will relinquish as of that date any
          positions that you hold with the Company.

2.        Severance Payment. The Company shall provide you with severance pay
          equivalent to your regular base salary (less all applicable federal,
          state, or local tax withholding, F.I.C.A., and any other applicable
          payroll deductions) through November 7, 1999, in accordance with the
          Company's regular pay practices. Such payments shall be made in
          installments corresponding to the regular pay periods of the Company
          and shall be mailed to you at 50 Hosmer Street, Acton, MA 01720. In
          addition, the Company will continue to offer you health insurance
          benefits on the terms currently offered to you and in effect at the
          time of execution of this agreement until the earlier of (i) the date
          on which you are eligible to participate in a health insurance plan
          offered by your next employer, or (ii) November 7, 1999.

3.        Monetary Consideration. In consideration of this letter agreement and
          your General Release, the Company has offered and you have accepted to
          act as a part-time employee of the Company, commencing November 8,
          1999 and terminating on the earlier of (i) at the close of business on
          March 31, 2002, or (ii) the day on which you have exercised all stock
          options which you will hold, if any, on November 8, 1999. In this
          position, you shall provide advice and assistance to the Company from
          time to time, as directed by management, for which you shall be paid
          at a rate of one hundred dollars ($100) per quarter (less all
          applicable federal, state or local tax withholding, F.I.C.A., and any
          other applicable payroll deductions) payable to you in accordance with
          the Company's bi-weekly payroll payment policies, but for which you
          shall receive no other benefits, except that your rights to
          participate in the Company's 1994 Stock Option Plan shall continue
          throughout the period of your part-time employment and except those
          benefits provided for below and/or are required by law. You
          acknowledge that you are not
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          otherwise entitled to the benefits described in this paragraph
          pursuant to the Employment Agreement or any other agreement or
          understanding. The parties understand and agree that your role as a
          part-time employee of the Company as provided under this paragraph
          does not preclude you from seeking or securing any full-time or other
          part-time employment after your separation date.

4.        Compensation Received to Date. On or before your separation date, you
          will be paid all compensation to which you are entitled for services
          rendered to the Company through your separation date, including any
          bonus earned for the Company's fiscal year ending March 31, 1999. You
          agree that you will make no claims for further compensation from the
          Company of any type, including bonus payments, commission payments,
          and vacation pay, except such sums as are provided for in this letter
          agreement.

5.        Outplacement Assistance. In further consideration of this letter
          agreement and your general release, the Company shall provide you with
          three (3) months of outplacement assistance services at a provider of
          such services selected by the Company. You acknowledge that you are
          not otherwise entitled to the benefits described in this paragraph
          pursuant to the Employment Agreement or any other agreement or
          understanding.

6.        Transfer of Responsibilities and Continuing Cooperation. You shall
          cooperate fully with the Company and its personnel on an as needed and
          as required basis to provide an orderly transfer of your duties and
          responsibilities and to provide continuing assistance in connection
          with on-going litigation and investigation matters. This cooperation
          includes timely compliance with all reasonable requests for
          information and other materials. This cooperation also includes timely
          compliance with all reasonable requests for information and assistance
          in connection with any and all on-going Company litigation,
          investigations, and legal inquiries. The Company agrees to reimburse
          you for any reasonable travel costs and expenses, including meals and
          lodging, incurred by you in connection with such compliance, and to
          make available to you upon reasonable request and notice pertinent
          records and documents related to such litigation, investigations and
          legal inquiries, which you agree will be used solely in relation
          thereto and for no other purpose. To the extent that you require legal
          representation in connection with these efforts that cannot be
          practically provided by the Company's counsel, the Company will
          reimburse you for any reasonable attorneys' fees and expenses related
          thereto.
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7.        Confidentiality. You agree that you will not, without the Company's
          prior written consent, reveal or disclose to any person or entity
          outside of the Company or use for your own benefit or for the benefit
          of any other person or entity, any confidential information concerning
          the business or affairs of the Company, or concerning the Company's
          customers, clients, or employees ("Confidential Information"). You
          further agree that you will refer all requests by any third party or
          the media regarding the Company, your employment, or your termination
          to the Company's General Counsel.

8.        Return of Property. On your separation date, you will return to the
          Company all property of the Company that is in your possession or
          under your control, including, without limitation, any and all files,
          documents and other information with respect to the Company's
          management, operations or customers, including all files, documents,
          or other information containing Confidential Information.
          Notwithstanding the foregoing, you may retain the fax/printer that the
          Company purchased on your behalf presently located in your home.

9.        Non-Disparagement. You further agree that you will not, at any time
          after the date hereof, make any remarks or comments, orally or in
          writing, to customers, potential customers, regulators or others,
          which or who have, or could reasonably be anticipated to have,
          business dealings with the Company, or to the media, which remarks or
          comments reasonably could be construed to be derogatory or disparaging
          to the Company or any of its shareholders, officers, directors,
          employees, attorneys or agents, or which reasonably could be
          anticipated to be damaging or injurious to the Company's reputation or
          good will or to the reputation or good will of any person associated
          with the Company.

10.       Remedies of the Company. You acknowledge that the restrictions
          contained in paragraphs 7 and 9 of this letter agreement are
          reasonable and necessary for the protection of the legitimate
          interests of the Company, that any violation of those restrictions
          would cause substantial injury to the Company, and that the Company
          would not have entered into this letter agreement without your
          agreement to be bound by those restrictions. In addition, you
          recognize and agree that the Company's remedy at law for material
          breaches of those restrictions is inadequate, that the damages for any
          material breach thereof would be irreparable, and that the Company
          shall be entitled to preliminary and permanent injunctive relief and
          specific performance thereof, in addition to any remedies it may have
          for monetary damages or other relief. You further recognize and agree
          that the covenants contained in paragraphs 7 and 9 shall be construed
          as independent of any other provision of this letter agreement and
          that the existence of any claim or cause of
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          action by you against the Company shall not constitute a defense to
          the enforcement by the Company of said covenants.

11.       Breach of Agreement. You understand and agree that any material breach
          of your obligations under this letter agreement will immediately
          render the Company's obligations and agreements hereunder null and
          void, and all payments pursuant to paragraph 3 hereof shall
          immediately cease and you shall repay to the Company forthwith all
          sums you have been paid or sums paid on your behalf pursuant to
          paragraph 3.

12.       References. In response to inquiries from your prospective employers,
          the Company shall state that it is the policy of the Company to verify
          only dates of employment and titles. Upon receipt from you of a
          proposed letter of reference, the Company agrees to execute and
          deliver such a letter to you, so long as such letter is acceptable to
          the Company in its exercise of reasonable judgment.

13.       General Release. In consideration of the good and valuable
          consideration set forth in this letter agreement, the receipt and
          sufficiency of which consideration you hereby acknowledge, and except
          for the rights granted under this separation agreement and any
          indemnification rights that you may have pursuant to the By-Laws of
          the Company and as provided by law, which rights, if any, are
          specifically excepted from the scope of this release, you, for
          yourself and your heirs, legal representatives, beneficiaries, assigns
          and successors in interest, hereby knowingly and voluntarily release,
          remise and forever discharge the Company and its successors, assigns,
          former, current or future shareholders, officers, directors,
          employees, agents, attorneys and representatives, whether in their
          individual or official capacities, from any and all actions or causes
          of action, suits, debts, claims, complaints, contracts, controversies,
          agreements, promises, damages, claims for attorneys' fees, punitive
          damages or reinstatement, judgments and demands whatsoever, in law or
          equity, you ever had from the beginning of the world to this date,
          including, without limitation, any claims under Title VII of the Civil
          Rights Act of 1964, 42 U.S.C.(Section).2000e et seq.; the Employee
          Retirement Income Security Act of 1974, as amended, 29
          U.S.C.(Section).1000 et seq., Massachusetts General Laws, Chapter
          151B; the Americans with Disabilities Act, 42 U.S.C.(Section).12101 et
          seq.; claims for breach of contract or based on tort; and any other
          statutory, regulatory or common law causes of action. You hereby
          acknowledge and understand that this is a General Release.

14.       Acknowledgment. You acknowledge and agree that you understand the
          meaning of this letter agreement, that you freely and voluntarily
          enter into it and the General
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          Release contained herein, and that the Company has advised you to
          consult an attorney of your choosing prior to signing this letter
          agreement. You agree that no fact, evidence, event, or transaction
          occurring before the execution of this letter agreement, which is
          currently unknown to you, but which may hereafter become known to you,
          shall affect in any manner the final and unconditional nature of the
          agreements and releases set forth herein.

15.       Miscellaneous. This letter agreement shall be construed in accordance
          with the laws of the Commonwealth of Massachusetts. A waiver of any
          breach of or failure to comply fully with any provision of this letter
          agreement by either party shall not operate or be construed as a
          waiver of any subsequent breach thereof or failure to comply. If any
          portion or provision of this letter agreement shall to any extent be
          deemed invalid or unenforceable, the remainder of this letter
          agreement, or the application of such portion or provision in
          circumstances other than those as to which it is held invalid or
          unenforceable, shall not be affected thereby and each portion and
          provision of this letter agreement shall be valid and enforceable to
          the fullest extent permitted.

      To avoid any possible misunderstanding, the Company intends this letter
agreement to be a comprehensive statement of the terms of your separation from
employment. This letter agreement supersedes any prior understanding or
statement made to you by the Company regarding your positions with the Company
or your arrangements with the Company for the period after your separation from
employment. For the same reason, any modifications of the terms set forth in
this letter agreement must be in writing and signed by you and by me on behalf
of the Company.
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      Please indicate your agreement to the terms of this letter agreement by
signing and dating the last page of the enclosed copy of this letter agreement,
and return it to me.

                                    Sincerely,

                                    /s/ L. Michael Hone

                                    L. Michael Hone
                                    President and Chief Executive Officer



AGREED TO AND EXECUTED UNDER SEAL THIS 31st day of March, 1998.


                                    /s/ Kathleen C. Little
                                    ---------------------------
                                    Kathleen C. Little