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                                                              Exhibit 10(f)(i)

                            INDEMNIFICATION AGREEMENT

         This INDEMNIFICATION AGREEMENT (the "Agreement") is made and entered
into as of this 4th day of May 2000, by and between NAHC, Inc., a Delaware
corporation (the "Company"), and David R. Burt, a resident of the Commonwealth
of Massachusetts ("Indemnitee").

                                    RECITALS:

         A. Indemnitee is willing to serve, continue to serve, and to take on
additional service for or on behalf of the Company on the condition that he be
indemnified to the fullest extent permitted by law.

         B. The Certificate of Incorporation of the Company requires the Company
to indemnify its directors and officers to the fullest extent permitted by law.

         C. Indemnitee is serving as a director of the Company.

                                   AGREEMENTS:

         NOW, THEREFORE, in consideration of the foregoing premises,
Indemnitee's agreement to serve as a member of the Board of Directors of the
Company, and the covenants contained in this Agreement, the Company and
Indemnitee hereby covenant and agree as follows:

         1. CERTAIN DEFINITIONS.

            (a) ACQUIRING PERSON: shall mean any Person other than (i) the
Company, (ii) any of the Company's Subsidiaries, (ii) any employee benefit plan
of the Company or of a Subsidiary of the Company or of a corporation owned
directly or indirectly by the stockholders of the Company in substantially the
same proportions as their ownership of stock of the Company, or (iv) any trustee
or other fiduciary holding securities under an employee benefit plan of the
Company or of a Subsidiary of the Company or of a corporation owned directly or
indirectly by the stockholders of the Company in substantially the same
proportions as their ownership of stock of the Company.

            (b) CHANGE OF CONTROL: shall be deemed to have occurred if:

                (i) an Acquiring Person is or becomes the "beneficial owner" (as
defined in Rule 13d-3 under the Securities Exchange Act of 1934, as amended (the
"Exchange Act")), directly or indirectly, of securities of the Company
representing thirty percent or more of the combined voting power of the then
outstanding Voting Securities of the Company; or

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                (ii) members of the Incumbent Board cease for any reason to
constitute at least a majority of the Board of Directors of the Company; or

                (iii) a public announcement is made of a tender or exchange
offer by any Acquiring Person for fifty percent or more of the outstanding
Voting Securities of the Company, and the Board of Directors of the Company
approves or fails to oppose that tender or exchange offer in its statements in
Schedule 14D-9 under the Exchange Act; or

                (iv) the stockholders of the Company approve a merger or
consolidation of the Company with any other corporation or partnership (or, if
no such approval is required, the consummation of such a merger or consolidation
of the Company); or

                (v) the stockholders of the Company approve a plan of complete
liquidation of the Company or an agreement for the sale or disposition by the
Company of all or substantially all the Company's assets (other than factoring
the Company's current receivables or escrows due), (or, if no such approval is
required, the decision by the Board of Directors of the Company to proceed with
such a liquidation, sale, or disposition in one transaction or series of related
transactions).

         (c) CLAIM: any threatened, pending, or completed action, suit, or
proceeding (including, without limitation, securities laws actions, suits, and
proceedings), or any inquiry or investigation (including discovery), whether
conducted by the Company or any other party, that Indemnitee in good faith
believes might lead to the institution of any action, suit, or proceeding,
whether civil, criminal, administrative, investigative, or other.

         (d) EXPENSES: all costs, expenses (including attorneys' and expert
witnesses' fees), and obligations paid or incurred in connection with
investigating, defending (including affirmative defenses and counterclaims),
being a witness in, or participating in (including on appeal), or preparing to
defend, be a witness in, or participate in, any Claim relating to any
Indemnifiable Event.

         (e) INCUMBENT BOARD: individuals who, as of May 4, 2000, constitute the
Board of Directors of the Company and any other individual who becomes a
director of the Company after that date and whose election or appointment by the
Board of Directors or nomination for election by the Company's stockholders was
approved by a vote of at least a majority of the directors then comprising the
Incumbent Board

         (f) INDEMNIFIABLE EVENT: an event or occurrence related to the fact
that Indemnitee is or was a director, officer, employee, agent, or fiduciary of
the Company, or is or was serving at the request of the Company as a director,
officer, employee, trustee, agent, or fiduciary of another corporation,
partnership, joint venture, employee benefit plan, trust, or other enterprise,
or by reason of any thing done or not done by Indemnitee in any such capacity.
For purposes of this Agreement, the Company agrees that Indemnitee's service on
behalf of or with respect to any Subsidiary of the Company shall be deemed to be
at the request of the Company.

         (g) PERSON: shall mean any person or entity of any nature whatsoever,
specifically including an individual, a firm, a company, a corporation, a
partnership, a trust or other entity. A Person, together with that Person's
Affiliates and Associates (as those terms are

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defined in Rule 12b-2 under the Exchange Act), and any Persons acting as a
partnership, limited partnership, joint venture, association, syndicate, or
other group (whether or not formally organized), or otherwise acting jointly or
in concert or in a coordinated or consciously parallel manner (whether or not
pursuant to any express agreement), for the purpose of acquiring, holding,
voting, or disposing of securities of the Company with such Person, shall be
deemed a single "Person."

         (h) POTENTIAL CHANGE OF CONTROL: shall be deemed to have occurred if
(i) the Company enters into an agreement, the consummation of which would result
in the occurrence of a Change of Control; (ii) any Person (including the
Company) publicly announces an intention to take or to consider taking actions
that, if consummated, would constitute a Change in Control; (iii) any Acquiring
Person who is or becomes the beneficial owner, directly or indirectly, of
securities of the Company representing 10% or more of the combined voting power
of the then outstanding Voting Securities of the Company increases his
beneficial ownership of such securities by 5% or more over the percentage so
owned by that Person on the date hereof; or (iv) the Board of Directors of the
Company adopts a resolution to the effect that, for purposes of this Agreement,
a Potential Change of Control has occurred.

         (i) REVIEWING PARTY: any appropriate person or body consisting of a
member or members of the Company's Board of Directors or any other person or
body appointed by the Board (including Special Counsel referred to in Section 3)
who is not a party to the particular Claim for which Indemnitee is seeking
indemnification.

         (j) SPECIAL COUNSEL: special, independent counsel selected by
Indemnitee and approved by the Company (which approval shall not be unreasonably
withheld), and who has not otherwise performed services for the Company or for
Indemnitee within the last three years (other than as Special Counsel under this
Agreement or similar agreements).

         (k) SUBSIDIARY: with respect to any Person, any corporation or other
entity of which a majority of the voting power of the voting equity securities
or equity interest is owned, directly or indirectly, by that Person.

         (l) VOTING SECURITIES: any securities that vote generally in the
election of directors or in the selection of any other similar governing body.

     2. BASIC INDEMNIFICATION AND EXPENSE REIMBURSEMENT ARRANGEMENT.

        (a) In the event Indemnitee was, is, or becomes a party to or witness or
other participant in, or is threatened to be made a party to or witness or other
participant in, a Claim by reason of (or arising in part out of) an
Indemnifiable Event, the Company shall indemnify Indemnitee to the fullest
extent permitted by law as soon as practicable but in any event no later than 30
days after written demand is presented to the Company, against any and all
Expenses, judgments, fines, penalties, and amounts paid in settlement (including
all interest, assessments, and other charges paid or payable in connection with
or in respect of such Expenses, judgments, fines, penalties, or amounts paid in
settlement) of or with respect to that Claim. Notwithstanding the foregoing, the
obligations of the Company under Section 2(a) shall be subject to the condition
that the Reviewing Party shall not have determined (in a written opinion, in any
case in

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which Special Counsel referred to in Section 3 hereof is involved) that
Indemnitee would not be permitted to be indemnified under applicable law.
Nothing contained in this Agreement shall require any determination under this
Section 2(a) to be made to the Reviewing Party prior to the disposition or
conclusion of the Claim against the Indemnitee; provided, however, that Expense
Advances shall continue to be made by the Company pursuant to and to the extent
required by the provisions of Section 2(b).

        (b) If so requested by Indemnitee, the Company shall pay any and all
Expenses incurred by Indemnitee (or, if applicable, reimburse Indemnitee for any
and all Expenses incurred by Indemnitee and previously paid by Indemnitee)
within two business days after such request (an "Expense Advance"). The Company
shall be obligated to make or pay an Expense Advance in advance of the final
disposition or conclusion of any Claim. In connection with any request for an
Expense Advance, if requested by the Company, Indemnitee or Indemnitee's counsel
shall submit an affidavit stating that the Expenses incurred were reasonable.
Any dispute as to the reasonableness of any Expense shall not delay an Expense
Advance by the Company, and the Company agrees that any such dispute shall be
resolved only upon the disposition or conclusion of the underlying Claim against
the Indemnitee. If, when, and to the extent that the Reviewing Party determines
that Indemnitee would not be permitted to be indemnified with respect to a Claim
under applicable law, the Company shall be entitled to be reimbursed by
Indemnitee and Indemnitee hereby agrees to reimburse the Company without
interest (which agreement shall be an unsecured obligation of Indemnitee) for
all related Expense Advances theretofore made or paid by the Company; provided,
however, that if Indemnitee has commenced legal proceedings in a court of
competent jurisdiction to secure a determination that Indemnitee should be
indemnified under applicable law, any determination made by the Reviewing Board
that Indemnitee would not be permitted to be indemnified under applicable law
shall not be binding and Indemnitee shall not be required to reimburse the
Company for any Expense Advance, and the Company shall be obligated to continue
to make Expense Advances, until a final judicial determination is made with
respect thereto (as to which all rights of appeal therefrom have been exhausted
or lapsed). If there has not been a Change of Control, the Reviewing Party shall
be selected by the Board of Directors of the Company. If there has been a Change
in Control, the Reviewing Party shall be advised by or shall be Special Counsel
referred to in Section 3 hereof, if and as Indemnitee so requests. If there has
been no determination by the Reviewing Party or if the Reviewing Party
determines that Indemnitee substantively would not be permitted to be
indemnified in whole or in part under applicable law, Indemnitee shall have the
right to commence litigation in any court in the states of Massachusetts,
Delaware or Pennsylvania having subject matter jurisdiction thereof and in which
venue is proper seeking an initial determination by the court or challenging any
such determination by the Reviewing Party or any aspect thereof, and the Company
hereby consents to service of process and to appear in any such proceeding. Any
determination by the Reviewing Party otherwise shall be conclusive and binding
on the Company and Indemnitee.

     3. CHANGE OF CONTROL. The Company agrees that, if there is a Change in
Control and if Indemnitee requests in writing that Special Counsel advise the
Reviewing Party or be the Reviewing Party, then the Company shall not deny any
indemnification payments (and Expense Advances shall continue to be paid by the
Company pursuant to Section 2(b)) that Indemnitee requests or demands under this
Agreement or any other agreement or law now or hereafter in effect relating to
Claims for Indemnifiable Events. The Company further agrees not to request or

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seek reimbursement from Indemnitee of any related Expense Advances unless, with
respect to a denied indemnification payment, Special Counsel has rendered its
written opinion to the Company and Indemnitee that the Company would not be
permitted under applicable law to pay Indemnitee such indemnification payment.
The Company agrees to pay the reasonable fees of Special Counsel referred to in
this Section 3 and to indemnify fully Special Counsel against any and all
expenses (including attorneys' fees), claims, liabilities, and damages arising
out of or relating to this Agreement or Special Counsel's engagement pursuant
hereto.

     4. ESTABLISHMENT OF TRUST. In the event of a Potential Change in Control,
the Company shall, upon written request by Indemnitee, create a trust for the
benefit of Indemnitee (the "Trust") and from time to time upon written request
of Indemnitee shall fund the Trust in an amount sufficient to satisfy any and
all Expenses reasonably anticipated at the time of each such request to be
incurred in connection with investigating, preparing for, and defending any
Claim relating to an Indemnifiable Event, and any and all judgments, fines,
penalties, and settlement amounts (including all interest, assessments, and
other charges paid or payable in connection with or in respect of such expenses,
judgments, fines, penalties, and settlement amounts) of any and all Claims
relating to an Indemnifiable Event from time to time actually paid or claimed,
reasonably anticipated, or proposed to be paid. The amount or amounts to be
deposited in the Trust pursuant to the foregoing funding obligation shall be
determined by the Reviewing Party, in any situation in which Special Counsel
referred to in Section 3 is involved. The terms of the Trust shall provide that,
upon a Change in Control, (i) the Trust shall not be revoked or the principal
thereof invaded, without the written consent of Indemnitee; (ii) the trustee of
the Trust shall advance, within two business days of a request by Indemnitee,
any and all expenses to Indemnitee (and Indemnitee hereby agrees to reimburse
the trust under the circumstances in which Indemnitee would be required to
reimburse the Company for Expense Advances under Section 2(b) of this
Agreement); (iii) the Trust shall continue to be funded by the Company in
accordance with the funding obligation set forth above; (iv) the trustee of the
Trust shall promptly pay to Indemnitee all amounts for which Indemnitee shall be
entitled to indemnification pursuant to this Agreement or otherwise; and (v) all
unexpended funds in that Trust shall revert to the Company upon a final
determination by the Reviewing Party or a court of competent jurisdiction, as
the case may be, that Indemnitee has been fully indemnified under the terms of
this Agreement. The trustee of the Trust shall be chosen by Indemnitee. Nothing
in this Section 4 shall relieve the Company of any of its obligations under this
Agreement.

     5. INDEMNIFICATION FOR ADDITIONAL EXPENSES. The Company shall indemnify
Indemnitee against any and all Expenses and, if requested by Indemnitee, shall
(within two business days of that request) advance those costs and expenses to
Indemnitee, that are incurred by Indemnitee in connection with any claims
asserted against or action brought by Indemnitee for (i) indemnification or
advance payment of Expenses by the Company under this Agreement or any other
agreement or provision of the Company's Certificate of Incorporation or Bylaws
now or hereafter in effect relating to Claims for Indemnifiable Events or (ii)
recovery under any directors' and officers' liability insurance policies
maintained by the Company, regardless of whether Indemnitee ultimately is
determined to be entitled to that indemnification, advance expense payment, or
insurance recovery, as the case may be.

     6. PARTIAL INDEMNITY. If Indemnitee is entitled under any provision of this
Agreement to indemnification by the Company for some or a portion of the
Expenses,

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judgments, fines, penalties, and amounts paid in settlement of a Claim but not,
however, for all of the total amount thereof, the Company shall nevertheless
indemnify Indemnitee for the portion thereof to which Indemnitee is entitled.
Moreover, notwithstanding any other provision of this Agreement, to the extent
that Indemnitee has been successful on the merits or otherwise in defense of any
or all Claims relating in whole or in part to an Indemnifiable Event or in
defense of any issue or matter therein, including dismissal without prejudice,
Indemnitee shall be indemnified against all Expenses incurred in connection
therewith.

     7. CONTRIBUTION.

        (a) CONTRIBUTION PAYMENT. To the extent the indemnification provided for
under any provision of this Agreement is determined (in the manner hereinabove
provided) not to be permitted under applicable law, then in the event Indemnitee
was, is or becomes a party to or witness or other participant in, or is
threatened to be made a party to or witness or other participant in, a Claim by
reason of (or arising in part out of) an Indemnifiable Event, the Company, in
lieu of Indemnifying Indemnitee, shall contribute to the amount of any and all
Expenses, judgments, fines, or penalties assessed against or incurred or paid by
Indemnitee on account of that Claim and any and all amounts paid in settlement
of that Claim (including all interest, assessments, and other charges paid or
payable in connection with or in respect of such Expenses, judgments, fines,
penalties, or amounts paid in settlement) for which such indemnification is not
permitted ("Contribution Amounts"), in such proportion as is appropriate to
reflect the relative fault with respect to the Indemnifiable Event giving rise
to the Contribution Amounts of Indemnitee, on the one hand, and of the Company
and any and all other parties (including officers and directors of the Company
other than Indemnitee) who may be at fault with respect to such Indemnifiable
Event (collectively, including the Company, the "Third Parties") on the other
hand.

        (b) RELATIVE FAULT. The relative fault of the Third Parties and the
Indemnitee shall be determined (i) by reference to the relative fault of
Indemnitee as determined by the court or other governmental agency assessing the
Contribution Damages or (ii) to the extent such court or other governmental
agency does not apportion relative fault, by the Reviewing Party (which shall
include Special Counsel) after giving effect to, among other things, the
relative intent, knowledge, access to information, and opportunity to prevent or
correct the applicable Indemnifiable Event and other relevant equitable
considerations of each party. The Company and Indemnitee agree that it would not
be just and equitable if contribution pursuant to this Section 7 were determined
by pro rata allocation or by any other method of allocation which does not take
account of the equitable considerations referred to in this Section 7(b).

     8. BURDEN OF PROOF. In connection with any determination by the Reviewing
Party or otherwise as to whether Indemnitee is entitled to be indemnified under
any provision of this Agreement or to receive contribution pursuant to Section 7
of this Agreement, the burden of proof shall be on the Company to establish that
Indemnitee is not so entitled.

     9. NO PRESUMPTION. For purposes of this Agreement, the termination of any
claim, action, suit, or proceeding, by judgment, order, settlement (whether with
or without court approval), or conviction, or upon a plea of nolo contendere, or
its equivalent, shall not create a presumption that Indemnitee did not meet any
particular standard of conduct or have any

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particular belief or that a court has determined that indemnification is not
permitted by applicable law.

     10. ACTION OF OTHERS. The knowledge and/or actions, or failure to act, of
any director, officer, agent, or employee of the Company shall not be imputed to
the Indemnitee for purposes of determining the right to indemnification under
this Agreement.

     11. INDEMNITEE'S INDIVIDUAL CAPACITY. The Company acknowledges that the
Indemnitee is undertaking to act as an officer or director of the Company at the
request of the Company and solely in the Indemnitee's individual capacity and
not in any capacity as a director, officer, member, partner, employee, trustee,
or other representative of any other corporation, partnership, association,
business trust, trust, or similar organization or entity. The Company covenants
and agrees to indemnify any such organization or entity from and against any and
all judgments, fines, or penalties assessed against or incurred or paid by such
organization or entity and any and all amounts paid in settlement (including all
interest, attorneys' and expert witnesses' fees, and other charges paid or
payable in connection with such judgments, fines, penalties, or amounts paid in
settlement) that relate to any action or inaction taken in the course of the
Indemnitee's duties as an officer or director of the Company.

     12. NON-EXCLUSIVITY. The rights of Indemnitee hereunder shall be in
addition to any other rights Indemnitee may have under the Company's Bylaws or
Certificate of Incorporation or the Delaware General Corporation Law or
otherwise. To the extent that a change in the Delaware General Corporation Law
(whether by statute or judicial decision) permits greater indemnification by
agreement than would be afforded currently under the Company's Bylaws or
Certificate of Incorporation and this Agreement, it is the intent of the parties
hereto that Indemnitee shall enjoy by this Agreement the greater benefits so
afforded by that change.

     13. LIABILITY INSURANCE. Except as otherwise agreed to by the Company and
Indemnitee in a written agreement, to the extent the Company maintains an
insurance policy or policies providing directors' and officers' liability
insurance, Indemnitee shall be covered by that policy or those policies, in
accordance with its or their terms, to the maximum extent of the coverage
available for any Company director or officer.

     14. PERIOD OF LIMITATIONS. No legal action shall be brought and no cause of
action shall be asserted by or on behalf of the Company or any affiliate of the
Company against Indemnitee or Indemnitee's spouse, heirs, executors, or personal
or legal representatives after the expiration of three years from the date of
accrual of that cause of action, and any claim or cause of action of the Company
or its affiliate shall be extinguished and deemed released unless asserted by
the timely filing of a legal action within that three-year period; provided,
however, that, if any shorter period of limitations is otherwise applicable to
any such cause of action, the shorter period shall govern.

     15. AMENDMENTS. No supplement, modification, or amendment of this Agreement
shall be binding unless executed in writing by both of the parties hereto. No
waiver of any of the provision of this Agreement shall be deemed or shall
constitute a waiver of any other provisions hereof (whether or not similar) nor
shall that waiver constitute a continuing waiver.

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     16. SUBROGATION. In the event of payment under this Agreement, the Company
shall, subject to the conflicting rights of an insurer pursuant to any policy
contemplated by Section 13 hereof, be subrogated to the extent of that payment
to all of the rights of recovery of Indemnitee, who shall execute all papers
required and shall do everything that may be necessary to secure those rights,
including the execution of the documents necessary to enable the Company
effectively to bring suit to enforce those rights.

     17. NO DUPLICATION OF PAYMENTS. The Company shall not be liable under this
Agreement to make any payment in connection with any claim made against
Indemnitee to the extent Indemnitee has otherwise actually received payment
(under an insurance policy, provision of the Company's Certificate of
Incorporation or Bylaws or otherwise) of the amounts otherwise indemnifiable
hereunder.

     18. BINDING EFFECT. This Agreement shall be binding upon and inure to the
benefit of and be enforceable by the parties hereto and their respective
successors, assigns (including any direct or indirect successor by purchase,
merger, consolidation, or otherwise to all or substantially all of the business
or assets of the Company), spouses, heirs, and personal and legal
representatives. This Agreement shall continue in effect regardless of whether
Indemnitee continues to serve as an officer or director of the Company or
another enterprise at the Company's request.

     19. SEVERABILITY. If any provision of this Agreement is held to be illegal,
invalid, or unenforceable under present or future laws effective during the term
hereof, that provision shall be fully severable; this Agreement shall be
construed and enforced as if that illegal, invalid, or unenforceable provision
had never comprised a part hereof; and the remaining provisions shall remain in
full force and effect and shall not be affected by the illegal, invalid, or
unenforceable provision or by its severance from this Agreement. Furthermore, in
lieu of that illegal, invalid, or unenforceable provision, there shall be added
automatically as a part of this Agreement a provision as similar in terms to the
illegal, invalid, or unenforceable provision as may be possible and be legal,
valid, and enforceable.

     20. GOVERNING LAW. This Agreement shall be governed by and construed and
enforced in accordance with the laws of the State of Delaware applicable to
contracts made and to be performed in that state without giving effect to the
principles of conflicts of laws.

     21. HEADINGS. The headings contained in this Agreement are for reference
purposes only and shall not affect in any way the meaning or interpretation of
this Agreement.

     22. NOTICES. Whenever this Agreement requires or permits notice to be given
by one party to the other, such notice must be in writing to be effective and
shall be deemed delivered and received by the party to whom it is sent upon
actual receipt (by any means) of such notice. Receipt of a notice by any officer
of the Company shall be deemed receipt of such notice by the Company.

     23. COUNTERPARTS. This Agreement may be executed in any number of
counterparts, each of which shall be deemed an original, but in making proof
hereof it shall not be necessary to produce or account for more than one such
counterpart.

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                 EXECUTED as of the date first written above.

                                   NAHC, INC.

                                   By: /s/ Robert E. Healy, Jr.
                                       ----------------------------------------
                                       Robert E. Healy, Jr.
                                       President

                                       /s/ David R. Burt
                                       ----------------------------------------
                                       David R. Burt, Indemnitee


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