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                                                                    Exhibit 10.6

                              Diomed Holdings, Inc.
                                 One Dundee Park
                                Andover, MA 01810

                                                              September 30, 2003

Verus Support Services, Inc.
520 Madison Avenue
New York, NY 10022
Attention: Ajmal Khan

                      Re: Agreement dated December 21, 2001

Dear Mr. Khan:

         Reference is made to the Consulting Services Agreement,  dated December
21,  2001,  and  to the  Indemnification  Agreement,  dated  December  21,  2001
(collectively,  the  "Agreement"),  and by and among Diomed  Holdings,  Inc. and
Diomed,  Inc.  (collectively,  the "Company") and Verus Support  Services,  Inc.
("Verus").  Capitalized  terms used herein and not otherwise  defined shall have
the meanings ascribed thereto in the Agreement.

         The  Company  and Verus  have  agreed to certain  terms and  conditions
regarding the termination of the Agreement as set forth herein,  effective as of
the date of this letter agreement.

         Within three (3) business  days after the  completion  of the Company's
equity financing that is scheduled to be completed during the fourth  generation
of 2003,  the  Company  will issue and  deliver  to Verus  500,000  shares  (the
"Shares") of Common Stock of Diomed Holdings, Inc. If the Company does not issue
and deliver the Shares to Verus,  then  notwithstanding  any other  provision of
this letter agreement to the contrary,  Verus shall have all rights and remedies
it now has under the Agreement.

         In  connection  with its  acceptance  of the  shares  of  Common  Stock
constituting  the Payment,  Verus  represents and warrants to, and covenants and
agrees with, the Company as follows:

              (a)  Without  limiting  Verus'  right to sell  such  Common  Stock
pursuant to an effective registration  statement,  Verus is acquiring the Common
Stock for its own account for  investment  only and not with a view  towards the
public  sale  or  distribution  thereof  and not  with a view to or for  sale in
connection with any distribution thereof.

              (b) Verus is (i) an "accredited Purchaser" as that term is defined
in Rule 501 of the General Rules and  Regulations  under the Common Stock Act by
reason  of Rule  501(a),  (ii)  experienced  in making  investments  of the kind
contemplated  hereby,  (iii)  able,  by reason  of the  business  and  financial
experience of its officers and  professional  advisors  (who are not  affiliated
with  or  compensated  in any way by the  Company  or any of its  affiliates  or
selling   agents),   to  protect  its  own  interests  in  connection  with  the
transactions  described  herein,  and (iv) able to afford the entire loss of its
investment in the Common Stock.


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Verus Support Services, Inc.
September 30, 2003
Page 2



              (c) All  subsequent  offers and sales of the Common Stock by Verus
shall be made only pursuant to registration of the Common Stock under the Common
Stock Act or pursuant to an exemption  from  registration  and  compliance  with
applicable states' Common Stock laws.

              (d) Verus  understands  that the Common Stock is being offered and
issued  to  it  in  reliance  on  specific   exemptions  from  the  registration
requirements  of United States  federal and state  securities  laws and that the
Company is relying upon the truth and accuracy of, and Verus'  compliance  with,
the representations,  warranties, agreements, acknowledgments and understandings
of Verus  set  forth  herein  in order to  determine  the  availability  of such
exemptions and the eligibility of Verus to acquire the Common Stock.

              (e) Verus has had the  opportunity  to  obtain  and to review  the
Company's (1) Annual  Reports on Form 10-KSB/A for the years ended  December 31,
2001 and 2002, (2) Quarterly Reports on Form 10-QSB for the quarters ended March
31, 2003 and June 30, 2003, (3) Registration Statement on Form SB-2 which became
effective  on October  24,  2002,  (4)  Prospectus  on Form 424B3 filed with the
Securities and Exchange Commission ("SEC") on October 30, 2002, (5) Registration
Statement  on Form SB-2 MEF filed with the SEC on  November  1, 2002,  (6) Proxy
Statement  on  Schedule  14A filed  with the SEC on July 2,  2003,  (7)  Current
Reports on Form 8-K filed with the SEC on October 22, 2002,  May 19, 2003,  July
29,  2003,  August 6, 2003 and  September  12,  2003 and (8)  Preliminary  Proxy
Statement on Schedule 14A filed with the SEC on September 15, 2003.

              (f) Verus is duly organized, validly existing and in good standing
under the laws of the  jurisdiction of its  organization.  This letter agreement
has been duly and validly authorized,  executed and delivered on behalf of Verus
and creates a valid and binding  agreement of Verus  enforceable  in  accordance
with its terms, subject as to enforceability to general principles of equity and
to  bankruptcy,  insolvency,  moratorium  and other  similar laws  affecting the
enforcement of creditors' rights generally.

              (g) Verus  acknowledges and agrees that the information  contained
in the  Agreement  and this  letter  agreement,  including  the  fact of  Verus'
acquisition  of the Common  Stock and the  information  regarding  Verus that is
contained in this  Agreement,  may be disclosed by the Company in its discretion
and Verus hereby gives the Company permission to make any such public disclosure
of said information.

              (h)  Verus  shall  timely  file  with  SEC all  necessary  filings
(including  without limitation filings on Form 4 and Schedule 13d/A) required to
be filed by Verus under the rules and  regulations of the SEC in connection with
Verus' acquisition of beneficial  ownership of the Common Stock pursuant to this
letter agreement.

              (i) Verus  certifies  that, to the best of its knowledge,  neither
Verus nor any of its  affiliates  has been  designated  as,  and is not owned or
controlled  by, a "suspected  terrorist"  as defined in  Executive  Order 13224.
Verus hereby represents,  warrants and agrees that no transaction  between Verus
and the Company contemplated by this letter agreement shall cause the Company to
be in violation of the Untied  States Bank Secrecy Act, the United  States Money
Laundering  Control  Act  of  1986  or the  Untied  States  International  Money
Laundering Abatement and Anti-Terrorist Financing Act of 2001.


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Verus Support Services, Inc.
September 30, 2003
Page 3


              (j) Verus  acknowledges  and  agrees  that  none of the  shares of
Common  Stock  constituting  the  Payment  may be sold,  assigned,  transferred,
pledged or otherwise disposed of, whether or not for value, except in compliance
with applicable law. Verus further acknowledges and agrees that each certificate
representing such shares of Common Stock shall be stamped or otherwise imprinted
with a legend  substantially  in the  following  form (in addition to any legend
required under applicable state securities laws or otherwise):

                  THE SHARES  REPRESENTED BY THIS CERTIFICATE HAVE BEEN ACQUIRED
                  FOR  INVESTMENT  AND  HAVE  NOT  BEEN  REGISTERED   UNDER  THE
                  SECURITIES ACT OF 1933 (THE  "SECURITIES  ACT").  THESE SHARES
                  MAY NOT BE SOLD, ASSIGNED,  TRANSFERRED,  PLEDGED OR OTHERWISE
                  DISPOSED  OF  IN  THE  ABSENCE  OF  SUCH  REGISTRATION  OR  AN
                  EXEMPTION THEREFROM UNDER THE SECURITIES ACT.

         In  consideration  of the Company's  agreement set forth above to issue
and deliver the Shares to Verus,  Verus, on behalf of itself and its affiliates,
hereby releases and absolutely forever discharges the Company and its respective
subsidiaries, affiliates, agents officers, directors, stockholders and attorneys
of and  from  all  claims,  demands,  penalties,  damages,  debts,  liabilities,
accounts, reckonings, obligations, costs, expenses, liens, actions and causes of
action of every kind and nature whatsoever,  which Verus now has, owns or holds,
or at any time owned or held,  or could,  shall or may  hereafter  have,  own or
hold,  based  upon or related to or by reason of the  Agreement  or any  related
agreement or contract.

         In  consideration of the foregoing  release by Verus,  the Company,  on
behalf of itself and its  affiliates,  hereby  releases and  absolutely  forever
discharges  Verus and each of its  subsidiaries,  affiliates,  agents  officers,
directors,   stockholders  and  attorneys  of  and  from  all  claims,  demands,
penalties,  damages,  debts,  liabilities,  accounts,  reckonings,  obligations,
costs,  expenses,  liens,  actions and causes of action of every kind and nature
whatsoever, which any of the Company or any of its subsidiaries now has, owns or
holds, or at any time owned or held, or could,  shall or may hereafter have, own
or hold,  based upon or related to or by reason of the  Agreement or any related
agreement or contract.

         This  letter may be signed in two or more  counterparts,  each of which
will be deemed an original,  but all of which  together will  constitute one and
the same  instrument.  This  agreement  may not be  amended  except by a writing
executed by all of the parties. This agreement shall be governed by the internal
laws of the State of New York, without regard to choice of law principles.

         The  parties  to  this  letter  agreement  have  executed  this  letter
agreement as of the date set forth above in the space provided below in order to
indicate their agreement to each of its terms.


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Verus Support Services, Inc.
September 30, 2003
Page 4


Sincerely,

Verus Support Services, Inc.        Diomed Holdings, Inc.
                                    (f/k/a Natexco Corporation)


By:     /s/  AJMAL KHAN             By: /s/ JAMES A. WYLIE, JR.
Name: Ajmal Khan                    Name: James A. Wylie, Jr.
Title: President                    Title: President and Chief Executive Officer

                                    Diomed, Inc.


                                    By: /s/ JAMES A. WYLIE, JR
                                    Name: James A. Wylie, Jr.
                                    Title: President and Chief Executive Officer