<PAGE>
                                                                    Exhibit 10.6

                               SECURITY AGREEMENT

                                                            DATE: March 30, 1999

         DM Management Company, of 25 Recreation Park Drive, Hingham,
Massachusetts (hereinafter called the DEBTOR), for valuable consideration,
receipt whereof is hereby acknowledged, hereby grants to Belknap County Economic
Development Council, Inc. , a non-profit corporation, organized and existing
under the laws of the State of New Hampshire and having a principal place of
business at 64 Court Street, Laconia, New Hampshire (hereinafter called the
SECURED Party), a security interest in the following property (including any
hereafter delivered to DEBTOR) and any and all additions, accessions, and
substitutions thereto or therefor and any or all proceeds thereof, viz: Specific
business assets located at: its Tilton, New Hampshire facility (the premises),
as set forth in SCHEDULE A attached and made a part hereof; to secure Debtors
obligations under the Loan Agreement between DEBTOR and SECURED PARTY of even
date herewith (the "Loan Agreement").


         DEBTOR hereby warrants and covenants:

1.   That except for the security interest granted hereby DEBTOR is, or to the
     extent that this agreement states that the Collateral is to be acquired
     after the date hereof, will be, the owner of the Collateral free from any
     adverse lien, security interest or other encumbrance; and that DEBTOR will
     defend the Collateral against all claims and demands of all persons, at any
     time claiming the same or any interest;

2.   That the Collateral is not used or bought primarily for personal, family or
     household purposes;

3.   That the Collateral will be kept at DEBTOR's place of business at 100 Birch
     Pond Drive, Tilton, New Hampshire; that DEBTOR will promptly notify SECURED
     PARTY of any change in the location of the Collateral within said State;
     and that DEBTOR will not remove the Collateral from said State without the
     written consent of SECURED PARTY;

4.   That no Financing Statement covering any Collateral or any proceeds hereof
     is on file in any public office, and at the request of SECURED PARTY,
     DEBTOR will join with SECURED PARTY in executing one or more Financing
     Statements pursuant to the Uniform Commercial Code in form satisfactory to
     SECURED PARTY and will pay the cost of filing the same in all public
     offices wherever filing is deemed by SECURED PARTY to be necessary or
     desirable;

5.   That DEBTOR will not sell or offer to sell or otherwise transfer the
     Collateral or any interest therein without the written consent of SECURED
     PARTY, except within the normal course of its business;

6.   That DEBTOR will have and maintain insurance at all times with respect to
     all Collateral against risks of fire (including so-called extended
     coverage), theft, and other risks as SECURED PARTY may require, containing
     such terms, in such form, for such periods and written by such companies as
     may be satisfactory to SECURED PARTY, such insurance to be payable to
     SECURED PARTY and DEBTOR as their interests may appear; that all policies
     of insurance shall provide for ten days' written minimum

<PAGE>
                                       2

    
     cancellation notice to SECURED PARTY and at request of SECURED PARTY
     copies of such policies shall be delivered to and held by it.

7.   That DEBTOR will keep the Collateral free from any adverse lien, security
     interest or encumbrance except those set forth on Exhibit A hereto
     ("permitted Encumbrances") and in good order and repair and will not waste
     or destroy the Collateral or any part thereof; that DEBTOR will not use the
     Collateral in violation of any statute or ordinance; that SECURED PARTY may
     examine and inspect the Collateral at any time, wherever located; and that
     the security interest set forth in this Security Agreement does not violate
     the provisions of any prior security agreements;

8.   That DEBTOR will pay promptly when due all taxes and assessments upon the
     Collateral or for its use or operation or upon this agreement or upon any
     note or notes evidencing the Obligations;

9.   At all reasonable times, and with reasonable notice, the DEBTOR will permit
     the SECURED PARTY, its accountants, auditors, or attorneys to make such
     examination and inspection of the DEBTOR's books, accounts, orders,
     correspondence and other records, relating to the collateral including the
     making of copies thereof or extracts therefrom, as the SECURED PARTY may
     request;

10.  At the request of the SECURED PARTY, the DEBTOR will execute and deliver to
     the SECURED PARTY such further documents and instruments of assurance and
     will do such further acts as the SECURED PARTY may deem necessary or
     advisable to assure to the SECURED PARTY all rights given or intended to be
     given to the SECURED PARTY hereby or hereunder;

         At its option, and upon five (5) days prior written notice to Debtor,
except for Permitted Encumbrances, SECURED PARTY may discharge taxes, liens or
security interests or other encumbrances at any time levied or placed on the
Collateral, and may pay for insurance on the Collateral and may pay for the
maintenance and preservation of the Collateral. DEBTOR agrees to reimburse
SECURED PARTY on demand for any payment made or any expense incurred by SECURED
PARTY pursuant to the foregoing authorization.

         Until an event of default under the Loan Agreement shall occur and be
continuing, DEBTOR may have possession of the Collateral and use it in any
lawful manner not inconsistent with this agreement and not inconsistent with any
policy of insurance thereon.

         DEBTOR shall be in default under this agreement upon the occurrence of
any event of default specified in the Loan Agreement.

         Upon the occurrence and continuance of such an event of default SECURED
PARTY may declare all obligations secured hereby immediately due and payable and
shall have the remedies of a secured party under the Uniform Commercial Code.
SECURED PARTY may require DEBTOR to assemble the Collateral and make it
available to SECURED PARTY at a place to be designated by SECURED PARTY which is
reasonably convenient to both parties. Whenever notification with respect to the
sale or other disposition of the Collateral is required by law, such
notification of the time and place of public sale, or of the date after which a
private sale or other intended disposition is to be made, shall be deemed
reasonable if mailed, postage prepaid, addressed to DEBTOR at the mailing
address hereinabove given at least ten (10) days before the time of such public
sale or the date after which any such private sale or other intended disposition
is to be made, as 


<PAGE>
                                       3


the case may be. Expenses of retaking, holding, preparing for sale, selling or
the like shall include SECURED PARTY's reasonable attorneys' fees and legal
expenses.

         No waiver by SECURED PARTY of any default shall operate as a waiver of
any other default or of the same default on a future occasion.

         All rights of SECURED PARTY hereunder shall inure to the benefit of its
successors and assigns; and all obligations of the DEBTOR shall bind its
successors or assigns.

         Schedule A may be amended hereafter by the submission from DEBTOR to
SECURED PARTY of a list of additional equipment purchased with proceeds of the
funds borrowed under the Loan Agreement.

         This agreement shall become effective when it is signed by DEBTOR. This
agreement and all rights and obligations hereunder, including matters of
construction, validity and performance, shall be governed by the law of New
Hampshire.


Executed on the day and year first above written.


                                    DEBTOR: DM Management Company

Steven D. Epstein                   /s/ Peter J. Tulp
------------------------            ---------------------------------------
witness                             Peter J. Tulp, VP Finance, Corporate
                                    Controller




                                    SECURED PARTY: Belknap County
                                    Economic Development Council, Inc.

Steven D. Epstein                    /s/ Eliza Leadbeater
------------------------            ---------------------------------------
witness                             By:  Eliza Leadbeater
                                    Its: Executive Director
                                    Hereunto Duly Authorized


<PAGE>


                                   DM MANAGEMENT
                                  BELKNAP CLY LOAN:
                      ASSETS SPECIFICALLY IDENTIFIED THRU 3/2/99
                                      SCHEDULE A


<TABLE>
<CAPTION>

      Asset                 Purchased From                        Invoice #                Amount              Total
      -----                 --------------                        ---------                ------              -----
<S>                       <C>                                 <C>                       <C>               <C>

                                                                                                           [ILLEGIBLE]

ergonomic workstations ergogenic technology                     quote 9807-03, invoice     4345,4348
  26 PR 770 CD-2 workstations @ $1,197 each                                      4355    $ 31,122.00
  14 (of 44 ttl) PR 770 CD-2 workstations @ $1,197 each       quote 9807-00 add          $ 16,758.00       [ILLEGIBLE]
  delivery on above   roberts white glove services                    102058051          $  1,406.00
                                                                                          -----------
                                                                                         $ 49,286.00      $    49,288.00
                                                                                          -----------
                                                                                          -----------
                                                                                                          $    80,886.00
</TABLE>


<PAGE>


                                  Exhibit A


     i)   Liens for taxes not yet due or liens for taxes being contested in 
good faith and by appropriate proceedings if adequate reserves with respect 
thereto are maintained on the books of DEBTOR in accordance with generally 
accepted accounting principles;

     ii)  Liens on property or assets of DEBTOR that were incurred in the 
ordinary course of business, such as landlords' and mechanics' liens and 
other similar liens arising in the ordinary course of business and that (x) 
do not in the aggregate materially detract from the value of the property or 
assets subject thereto or materially impair the use thereof in the operation 
of the business of DEBTOR or (y) that are being contested in good faith by 
appropriate proceedings, which proceedings have the effect of preventing the 
forfeiture or sale of the property or assets subject to such lien; and

     iii) Subordinated liens of Citizens Bank of Massachusetts


<PAGE>

         UNIFORM COMMERCIAL CODE -- FINANCING STATEMENT -- FORM UCC-1

        IMPORTANT -- READ INSTRUCTIONS ON BACK BEFORE FILLING OUT FORM.

This FINANCING STATEMENT is presented to a filing officer for filing pursuant 
to the Uniform Commerical Code.

<TABLE>
-------------------------------------------------------------------------------------------------------------------------------
<S>                                    <C>                                  <C>
1. Debtor(s) (Last Name First) and     2. Secured Party(ies) Name(s)        3. For Filing Officer: Date, Time, 
   Address(es).                           and Address(es).                     No. Filing Office

   DM Management Company                  Belknap County Economic
   25 Recreation Park Drive               Development Council
   Hingham, MA  02043                     64 Court Street
                                          Laconia, NH  03246

/ /  The Debtor is a Transmitting Utility
-------------------------------------------------------------------------------------------------------------------------------
  4. This Financing Statement covers the following types (or items) of property:

     Equipment more particularly described in Schedule A attached and 
     located at:

              100 Birch Pond Drive
              Tilton, NH  03276

                                                -------------------------------------------------------------------------------
/ /  Products of the Collateral are             5. Name of a Record Owner: Birch Pond Realty Corporation
     also covered.
-------------------------------------------------------------------------------------------------------------------------------
6. (a) / / The described crops are              7. Describe Real Estate Here:         8. / / This Statement is to be indexed
           growing or are to be grown on: -                                                  in the Real Estate Records
   (b) / / The described goods are or are to
           be fixtures on: -
   (c) / / The lumber to be cut or minerals
           or the like (including oil and gas)
           is on: -
        *  Describe Real Estate in Box 7.
-------------------------------------------------------------------------------------------------------------------------------
9.  This Statement is filed without the debtor's signature to perfect a security interest in collateral (see instruction No. 9)
-------------------------------------------------------------------------------------------------------------------------------
10. Filed with:  NH Secretary of State                                           11. No. of Additional Sheets Presented:  1
-------------------------------------------------------------------------------------------------------------------------------
                 DM Management Company                      Belknap County Economic Development Council
         -------------------------------------------        ------------------------------------------------------

         By: /s/ Peter J. Tulp                              By: /s/  Eliza Leadbeder
            ----------------------------------------           ---------------------------------------------------
            Signature(s) of Debtor(s) or Assignor(s)           Signature(s) of Secured Party(ies) or Assignee(s)
                                                                             STATE OF NEW HAMPSHIRE

     (1) FILING OFFICER COPY -- ALPHABETICAL
         DM Management Company                   Belknap County Economic
         25 Recreation Park Drive                Development Council
         Hingham, MA  02043                      64 Court Street
                                                 Laconia, NH  03246

/ / The Debtor is a Transmitting Utility
-------------------------------------------------------------------------------------------------------------------------------
4.  This Financing Statement covers the following types (or items) of property: 

    Equipment more particularly described in Schedule A attached and located at:
           100 Birch Pond Drive
           Tilton, NH  03276

                                                -------------------------------------------------------------------------------
/ / Products of the Collateral are              5. Name of a Record Owner: Birch Pond Realty Corporation
    also covered. 
-------------------------------------------------------------------------------------------------------------------------------
6. (a) / / The described crops are              7. Describe Real Estate Here:         8. / / This Statement is to be indexed
           growing or are to be grown on: -                                                  in the Real Estate Records
   (b) / / The described goods are or are to
           be fixtures on: -
   (c) / / The lumber to be cut or minerals
           or the like (including oil and gas)
           is on: -
        *  Describe Real Estate in Box 7.
-------------------------------------------------------------------------------------------------------------------------------
9.  This Statement is filed without the debtor's signature to perfect a security interest in collateral (see instruction No. 9)
-------------------------------------------------------------------------------------------------------------------------------
10. Filed with:  Belknap County Registry of Deeds                                 11. No. of Additional Sheets Presented:  1
-------------------------------------------------------------------------------------------------------------------------------
                 DM Management Company                      Belknap County Economic Development Council
         -------------------------------------------        ------------------------------------------------------

         By: /s/ Peter J. Tulp                              By: /s/  Eliza Leadbeder
            ----------------------------------------           ---------------------------------------------------
            Signature(s) of Debtor(s) or Assignor(s)           Signature(s) of Secured Party(ies) or Assignee(s)
                                                                             STATE OF NEW HAMPSHIRE
</TABLE>

<PAGE>

         UNIFORM COMMERCIAL CODE -- FINANCING STATEMENT -- FORM UCC-1

        IMPORTANT -- READ INSTRUCTIONS ON BACK BEFORE FILLING OUT FORM.

This FINANCING STATEMENT is presented to a filing officer for filing pursuant 
to the Uniform Commerical Code.

<TABLE>
-------------------------------------------------------------------------------------------------------------------------------
<S>                                    <C>                                  <C>
1. Debtor(s) (Last Name First) and     2. Secured Party(ies) Name(s)        3. For Filing Officer: Date, Time, 
   Address(es).                           and Address(es).                     No. Filing Office

   DM Management Company                  Belknap County Economic
   25 Recreation Park Drive               Development Council
   Hingham, MA  02043                     64 Court Street
                                          Laconia, NH  03246

/ /  The Debtor is a Transmitting Utility
-------------------------------------------------------------------------------------------------------------------------------
  4. This Financing Statement covers the following types (or items) of property:

     Equipment more particularly described in Schedule A attached and 
     located at:

              100 Birch Pond Drive
              Tilton, NH  03276

                                                -------------------------------------------------------------------------------
/ /  Products of the Collateral are             5. Name of a Record Owner: Birch Pond Realty Corporation
     also covered.
-------------------------------------------------------------------------------------------------------------------------------
6. (a) / / The described crops are              7. Describe Real Estate Here:         8. / / This Statement is to be indexed
           growing or are to be grown on: -                                                  in the Real Estate Records
   (b) / / The described goods are or are to
           be fixtures on: -
   (c) / / The lumber to be cut or minerals
           or the like (including oil and gas)
           is on: -
        *  Describe Real Estate in Box 7.
-------------------------------------------------------------------------------------------------------------------------------
9.  This Statement is filed without the debtor's signature to perfect a security interest in collateral (see instruction No. 9)
-------------------------------------------------------------------------------------------------------------------------------
10. Filed with:  Town of Tilton                                                   11. No. of Additional Sheets Presented:  1
-------------------------------------------------------------------------------------------------------------------------------
                 DM Management Company                      Belknap County Economic Development Council
         -------------------------------------------        ------------------------------------------------------

         By: /s/ Peter J. Tulp                             By: /s/  Eliza Leadbeder
            ----------------------------------------           ---------------------------------------------------
            Signature(s) of Debtor(s) or Assignor(s)           Signature(s) of Secured Party(ies) or Assignee(s)
                                                                             STATE OF NEW HAMPSHIRE

     (1) FILING OFFICER COPY -- ALPHABETICAL

</TABLE>