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                                    EXHIBIT A

      This Exhibit A provides for certain of the substantive terms and
provisions regarding, among other things, the interest rate, interest repayment,
and selection and conversion of optional interest rates for the Loans
established pursuant to the First Amendment To Unsecured Revolver Loan Agreement
to which this document is attached as an Exhibit (the "Loan Agreement"). The
terms and provisions of this Exhibit A are specifically incorporated by
reference into the Loan Agreement.

1.    The following terms as used in this Exhibit A and the Loan Agreement shall
      have the meanings set forth below:

      Base Rate. The higher of (a) the annual rate of interest announced from
time to time by the Lender at its head office in Boston, Massachusetts as its
"base rate" and (b) one half of one percent (1/2%) above the overnight federal
funds effective rate as published by the Board of Governors of the Federal
Reserve System, as in effect from time to time.

      Business Day. Any day on which the Lender is open for the transaction of
banking business in Boston, Massachusetts and, in case of LIBOR Rate Loans, also
a day which is a LIBOR Business Day.

      Conversion Request. A notice given by the Borrower to the Lender of (i)
its initial selection of an interest rate option for an Advance in accordance
with Paragraph 5, herein, or (ii) its election to convert or continue an
interest rate option for a Loan in accordance with Paragraph 6, herein.

      Convert, Conversion and Converted. The conversion of a Loan from one Type
to Loans of another Type.

      Domestic Rate. For any Interest Period with respect to each Domestic Rate
Loan, floating at the per annum rate equal to the Base Rate. The Domestic Rate
shall be adjusted automatically on any change in the Base Rate, such that any
change in the Domestic Rate resulting therefrom shall become effective as of the
opening of business on the day on which such change in the Base Rate became
effective.

      Domestic Rate Loan. All or any portion of any Advance or the Loan which
bears interest at the Domestic Rate.

      Eurocurrency Reserve Rate. For any day with respect to a LIBOR Rate Loan,
the maximum rate (expressed as a decimal) at which any lender subject thereto
would be required to maintain reserves under Regulation D of the Board of
Governors of the Federal Reserve System (or any successor or similar regulations
relating to such reserve requirements) against "Eurocurrency


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Liabilities" (as that term is used in Regulation D), if such liabilities were
outstanding. The Eurocurrency Reserve Rate shall be adjusted automatically on
and as of the effective date of any change in the Eurocurrency Reserve Rate.

      Interest Payment Date. (a) As to any Loan, the first day of each calendar
month commencing with the calendar month following the calendar month which
includes the date of the Advance of such Loan; and (b) as to any LIBOR Rate
Loan, the last day of each Interest Period.

      Interest Period. With respect to each Loan, (a) initially, the period
commencing on the date of the Advance of such Loan and ending on the last day of
one of the periods set forth below (i) for any Domestic Rate Loan, the last day
of the calendar month; and (ii) as selected by the Borrower in a Conversion
Request, for any LIBOR Rate Loan, 1, 2, 3, or 6 months; and (b) thereafter, each
period commencing on the last day of the next preceding Interest Period
applicable to such Loan and ending on the last day of one of the periods set
forth above, as selected by the Borrower in a Conversion Request; provided that
all of the foregoing provisions relating to Interest Periods are subject to the
following:

            (A) if any Interest Period with respect to a LIBOR Rate Loan would
      otherwise end on a day that is not a LIBOR Business Day, that Interest
      Period shall be extended to the next succeeding LIBOR Business Day unless
      the result of such extension would be to carry such Interest Period into
      another calendar month, in which event such Interest Period shall end on
      the immediately preceding LIBOR Business Day;

            (B) if any Interest Period with respect to a Domestic Rate Loan
      would end on a day that is not a Business Day, that Interest Period shall
      end on the next succeeding Business Day;

            (C) if the Borrower shall fail to give notice as provided in
      Paragraph 6, herein, the Borrower shall be deemed to have requested a
      conversion of the affected LIBOR Rate Loan to a Domestic Rate Loan on the
      last day of the then current Interest Period with respect thereto;

            (D) any Interest Period relating to any LIBOR Rate Loan that begins
      on the last LIBOR Business Day of a calendar month (or on a day for which
      there is no numeri cally corresponding day in the calendar month at the
      end of such Interest Period) shall end on the last LIBOR Business Day of a
      calendar month; and



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            (E) any Interest Period relating to any LIBOR Rate Loan that would
      otherwise extend beyond the Maturity Date shall end on the Maturity Date.

      LIBO Rate. For any Interest Period with respect to a LIBOR Rate Loan, the
interest rate per annum (rounded upwards to the next highest 1/16 of 1%)
determined by the Lender pursuant to the following formula:

                  Euro Rate   =   LIBO Bid Rate
                                  --------------------------------
                                  1.00 - Eurocurrency Reserve Rate

      LIBO Bid Rate. For any Interest Period with respect to a LIBOR Rate Loan,
the annual rate of interest determined by the Lender on the second Business Day
prior to the first day of such Interest Period to be the rate at which deposits
in U.S. dollars are offered to the Lender by prime banks in whatever Eurodollar
interbank market may be selected by the Lender in its sole discretion, acting in
good faith, at the time of determination and in accordance with the usual
practice in such market for delivery on the first day of such Interest Period
for the number of days comprised therein and in an amount equal (as nearly as
may be) to the principal amount of such LIBOR Rate Loan.

      LIBOR Business Day. Any day on which commercial banks are open for
international business (including dealings in Dollar deposits) in London or such
other eurodollar interbank market as may be selected by the Lender in its sole
discretion acting in good faith.

      LIBOR Rate. For any Interest Period with respect to a LIBOR Rate Loan, an
interest rate per annum equal at all times during such Interest Period to the
(i) LIBO Rate plus (ii) One percent (1.00%).

      LIBOR Rate Loan. All or any portion of an Advance or the Loan bearing
interest calculated by reference to the LIBOR Rate.

      Type of Loan. A Domestic Rate Loan or a LIBOR Rate Loan, as the case may
be.

2.    Any and all terms which are defined in the Loan Agreement shall when used
      herein have the meaning set forth in the Loan Agreement, unless otherwise
      defined herein.

3.    The Loan shall bear interest as follows:

      a.    For each Interest Period:

            i.    To the extent that all or any portion of the Loan is a
                  Domestic Rate Loan, such portion shall bear


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                  interest during such Interest Period at the floating rate
                  equal to the Domestic Rate.

            ii.   To the extent that all or any portion of the Loan is a LIBOR
                  Rate Loan, such portion shall bear interest during such
                  Interest Period at the LIBOR Rate determined for such Interest
                  Period.

4.    The Borrower promises to pay interest on the Loan in arrears on each
      Interest Payment Date applicable to such Interest Period.

5.    The Borrower agrees that each request submitted to the Lender requesting
      an Advance shall be accompanied by a written notice of Borrower (the
      "Conversion Request") specifying (i) the requested Type of Loan comprising
      such Advance, (ii) in the case of an Advance comprised of any LIBOR Rate
      Loan, the initial Interest Period; and (iii) the amount of each Type of
      Loan; provided, however, that each LIBOR Rate Loan shall be in an amount
            --------  -------
      of $100,000.00 or integral multiple thereof. A Conversion Request with
      respect to a LIBOR Rate Loan shall be irrevocable and binding on Borrower.
      If no Conversion Request is given by Borrower to the Lender with respect
      to any request for an Advance, the Borrower shall be deemed to have
      selected a Domestic Rate Loan.

6.    Upon notice given by Borrower to the Lender not later than 12:00 noon
      (Boston time) (1) in the case of Conversions into Domestic Rate Loans, on
      the date of the proposed Conversion, and (2) in the case of Conversions
      into LIBOR Rate Loans on the third Business Day prior to the date of the
      proposed Conversion, the Borrower may Convert, on any Business Day, Loans
      of one Type made to the Borrower into Loans of another Type,
      provided, however, that (a) any Conversion of LIBOR Rate Loans may be made
      --------  -------
      only on the last day of the respective Interest Period for such Loans, (b)
      any Loan Converted to a LIBOR Rate Loan shall be in an amount of
      $100,000.00 or integral multiple thereof, and (c) no Advance may be
      Converted to a LIBOR Rate Loan when any Default or Event of Default has
      occurred and is continuing. Each such Conversion Request shall be by
      telephone, telecopy, telex or cable, in each case confirmed immediately in
      writing in the manner specified for notices herein, and shall, within the
      restrictions specified above, specify (i) the date of such Conversion,
      (ii) the Loans to be Converted, and (iii) if such Conversion is to LIBOR
      Rate Loan the duration of the initial Interest Period for such Loans. Each
      Conversion Request with respect to LIBOR Rate Loans shall be irrev ocable
      and binding on the Borrower.


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7.    If after giving a Conversion Request, the Borrower fails to borrow or
      Convert any LIBOR Rate Loan, the Borrower shall indemnify the Lender
      against any loss or expense incurred by the Lender as a result of such
      failure including, without limitation, any loss or expense incurred by
      reason of the liquidation or reemployment of deposits or other funds
      acquired by the Lender to fund or maintain an Advance to be made by the
      Lender and the compensation as provided for in Paragraph 12, herein.

8.    Any Loans of any Type may be continued as such upon the expiration of an
      Interest Period with respect thereto by compliance by the Borrower with
      the notice provisions contained in Paragraph 6, above; provided that no
                                                             --------
      LIBOR Rate Loan may be continued as such when any Default or Event of
      Default has occurred and is continuing, but shall be automatically
      converted to a Domestic Rate Loan on the last day of the first Interest
      Period relating thereto ending during the continuance of any Default or
      Event of Default of which the officers of the Lender active upon the
      Borrower's account have actual knowledge.

9.    In the event that the Borrower does not notify the Lender of its election
      under Paragraph 6, herein, in a timely manner with respect to any Loan
      upon the expiration of the applicable Interest Period, such Loan shall be
      automatically converted to a Domestic Rate Loan at the end of the
      applicable Interest Period.

10.   Notwithstanding anything to the contrary contained herein, in no event may
      the Borrower select more than five (5) Interest Periods to be in effect at
      any one time for any particular Type of Loan.

11.   Each determination of an interest rate by the Lender pursuant hereto shall
      be conclusive and binding upon the Borrower in the absence of manifest
      error.

12.   The Borrower agrees to indemnify the Lender and to hold the Lender
      harmless from and against any loss, cost or expense (including loss of
      anticipated profits) that the Lender may sustain or incur as a consequence
      of (a) an Event of Default by the Borrower in payment of the principal
      amount of or any interest on any LIBOR Rate Loans as and when due and
      payable, including any such loss or expense arising from interest or fees
      payable by the Lender to lenders of funds obtained by it in order to
      maintain its LIBOR Rate Loans, (b) an Event of Default by the Borrower in
      making a borrowing or conversion after the Borrower has given (or is
      deemed to have given) a Conversion Request, or (c) the making of any
      payment of any LIBOR Rate Loan or the making of any conversion of any such
      Loan to a Domestic Rate Loan



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      on a day that is not the last day of the applicable Interest Period with
      respect thereto, whether due to voluntary prepayment, payment realized
      from the Collateral or any Guarantor after the occurrence of an Event of
      Default, or otherwise, including interest or fees payable by the Lender to
      lenders of funds obtained by it in order to maintain any such Loans. Such
      loss shall include, without limitation, an amount calculated as follows:

      a.    First, the Lender shall determine the amount by which (i) the total
            amount of interest which would have otherwise accrued hereunder on
            each installment of principal so paid or not borrowed, during the
            period beginning on the date of such payment or failure to borrow
            and ending on the date such installment would have been due (the
            "Reemployment Period"), exceeds (ii) the total amount of interest
            which would accrue, during the Reemployment Period, on any readily
            marketable bond or other obligation of the United States of America
            designated by the Lender in its sole discretion at or about the time
            of such payment, such bond or other obligation of the United States
            of America to be in an amount equal (as nearly as may be) to the
            amount of principal so paid or not borrowed and to have a maturity
            comparable to the Reemployment Period, and the interest to accrue
            thereon to take account of amortization of any discount from par or
            accretion of premium above par at which the same is selling at the
            time of designation. Each sum amount is hereafter referred to as an
            "Installment Amount".

      b.    Second, each Installment Amount shall be treated as payable as of
            the date on which the related principal installment would have been
            payable by the Borrower had such principal installment not been
            prepaid or not borrowed.

      c.    Third, the amount to be paid on each such date shall be the present
            value of the Installment Amount determined by discounting the amount
            thereof from the date on which such Installment Amount is to be
            treated as payable, at the same annual interest rate as that payable
            upon the bond or other obligation of the United States of America
            designated as aforesaid by the Lender.

13.   In the event, prior to the commencement of any Interest Period relating to
      any LIBOR Rate Loan, the Lender shall determine that adequate and
      reasonable methods do not exist for ascertaining the Euro Rate that would
      otherwise determine the rate of interest to be applicable to any LIBOR
      Rate Loan during any Interest Period, the Lender shall


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      forthwith give notice of such determination (which shall be conclusive and
      binding on the Borrower) to the Borrower. In such event (a) any Conversion
      Request with respect to LIBOR Rate Loans shall be automatically withdrawn
      and shall be deemed a request for Domestic Rate Loans, (b) each LIBOR Rate
      Loan will automatically, on the last day of the then current Interest
      Period thereof, become a Domestic Rate Loan, and (c) the obligations of
      the Lender to make LIBOR Rate Loans shall be suspended until the Lender
      determines that the circumstances giving rise to such suspension no longer
      exist, whereupon the Lender shall so notify the Borrower.

14.   Notwithstanding any other provisions herein, if any present or future law,
      regulation, treaty or directive or in the interpretation or application
      thereof shall make it unlawful for the Lender to make or maintain LIBOR
      Rate Loans, the Lender shall forthwith give notice of such circumstances
      to the Borrower and thereupon (a) the commitment of the Lender to make
      LIBOR Rate Loans or convert Loans of another type to LIBOR Rate Loans
      shall forthwith be suspended and (b) the LIBOR Rate Loans then outstanding
      shall be converted auto matically to Domestic Rate Loans on the last day
      of each Interest Period applicable to such LIBOR Rate Loans or within such
      earlier period as may be required by law. The Borrower hereby agrees
      promptly to pay the Lender, upon demand, any additional amounts necessary
      to compensate the Lender for any costs incurred by the Lender in making
      any conversion in accordance with this section, including any interest or
      fees payable by the Lender to lenders of funds obtained by it in order to
      make or maintain its LIBOR Rate Loans hereunder and any amount payable as
      provided in Paragraph 12, herein.

15.   The Borrower shall have the right at any time to prepay the Note on or
      before the Maturity Date, as a whole, or in part, subject to the following
      limitations:

      a.    For any Domestic Rate Loan, without premium or penalty, provided
                                                                    --------
            that any amount prepaid shall be accompanied by accrued interest on
            the principal repaid to the date of payment;

      b.    For any LIBOR Rate Loan, upon not less than three (3) Business Days'
            prior written notice to the Lender, without penalty, provided that
                                                                 --------
            (1) each partial prepayment shall be in the principal amount of
            $100,000.00 or an integral multiple thereof, (2) if such prepayment
            is on any day other than the last day of the Interest Period
            relating thereto, such amount prepaid shall be accompanied by any
            additional amounts necessary to compensate the Lender for any costs



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            incurred by the Lender in accordance with Paragraph 12, herein,
            including any interest or fees payable by the Lender to lenders of
            funds obtained by it in order to make or maintain its LIBOR Rate
            Loans hereunder and (3) any amount prepaid shall be accompanied by
            accrued interest on the principal repaid to the date of payment.

      c.    If the Loan Documents provide at the time of prepayment for periodic
            principal payments on the Loan, any prepayment of principal shall be
            applied against the scheduled installments of principal due on the
            Loan in the inverse order of maturity. No amount repaid with respect
            to the Loan may be reborrowed.

      d.    In the event that at the time of any such prepayment Loans are
            outstanding of more than one Type, the amount prepaid shall be
            applied first to any Domestic Rate Loan prior to application to any
            LIBOR Rate Loans.

      e.    Any premium due hereunder upon such prepayment shall be due and
            payable upon any prepayment whatsoever, whether voluntary or
            involuntary, to the extent permitted by law, and after acceleration
            of the unpaid principal balance of the Loan after the occurrence of
            an Event of Default.

16.   If any present or future applicable law, which expression, as used herein,
      includes statutes, rules and regulations thereunder and interpretations
      thereof by any competent court or by any governmental or other regulatory
      body or official charged with the administration or the interpretation
      thereof and requests, directives, instructions and notices at any time or
      from time to time hereafter made upon or otherwise issued to the Lender by
      any central bank or other fiscal, monetary or other authority (whether or
      not having the force of law), shall:

            (a) subject the Lender to any tax, levy, impost, duty, charge, fee,
      deduction or withholding of any nature with respect to this Agreement, the
      other Loan Documents, or the Loans (other than taxes based upon or
      measured by the income or profits of the Lender), or

            (b) materially change the basis of taxation (except for changes in
      taxes on income or profits) of payments to the Lender of the principal of
      or the interest on any Loans or any other amounts payable to the Lender
      under this Agreement or the other Loan Documents, or

            (c) impose or increase or render applicable (other than to the
      extent specifically provided for elsewhere in


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      this Agreement) any special deposit, reserve, assessment, liquidity,
      capital adequacy or other similar requirements (whether or not having the
      force of law) against assets held by, or deposits in or for the account
      of, or loans by, or commitments of an office of the Lender, or

            (d) impose on the Lender any other conditions or re quirements with
      respect to this Agreement, the other Loan Documents, the Loan, or any
      class of loans or commitments of which any Loan forms a part;

and the result of any of the foregoing is

            (i) to increase the cost to the Lender of making, funding, issuing,
      renewing, extending or maintaining any of the Loans, or

            (ii) to reduce the amount of principal, interest or other amount
      payable to the Lender hereunder on account of any of the Loans, or

            (iii) to require the Lender to make any payment or to forego any
      interest or other sum payable hereunder, the amount of which payment or
      foregone interest or other sum is calculated by reference to the gross
      amount of any sum receivable or deemed received by the Lender from the
      Borrower hereunder,

then, and in each such case, the Borrower will, upon demand made by the Lender
at any time and from time to time and as often as the occasion therefor may
arise, pay to the Lender such additional amounts as will be sufficient to
compensate the Lender for such additional cost, reduction, payment or foregone
interest or other sum.

17.   Capital Adequacy. If the Lender shall have determined that the adoption of
      any applicable law, rule, regulation, guideline, directive or request
      (whether or not having force of law) regarding capital requirements, or
      the interpretation or administration thereof by any governmental
      authority, central bank or comparable agency charged with the
      interpretation or administration thereof, or compliance by the Lender with
      any of the foregoing imposes or increases a requirement by the Lender to
      allocate capital resources to the Loans made, or to be made, hereunder,
      which has or would have the effect of reducing the return on the Lender's
      capital to a level below that which the Lender could have achieved (taking
      into consideration the Lender's then existing policies with respect to
      capital adequacy and assuming full utilization of the Lender's capital)
      but for such adoption, change or compliance, by any amount deemed by the
      Lender to be material: (i) the Lender shall promptly

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      after its determination of such occurrence give notice thereof to the
      Borrower; and (ii) the Borrower shall pay to the Lender as an additional
      fee from time-to-time on demand such amount as the Lender certifies to be
      the amount that will compensate it for such reduction. In determining such
      amounts, the Lender may use any reasonable averaging and attribution
      methods.

18.   All computations of interest on the Loans and of other fees to the extent
      applicable shall be based on a 360-day year and paid for the actual number
      of days elapsed. Except as otherwise provided in the definition of the
      term "Interest Period" with respect to LIBOR Rate Loans, whenever a
      payment hereunder or under any of the other Loan Documents becomes due on
      a day that is not a Business Day, the due date for such payment shall be
      extended to the next succeeding Business Day, and interest shall accrue
      during such extension.



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