Document:

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                                                                    EXHIBIT 10.6

                       THE INVESTOR RELATIONS GROUP, INC.

                               LETTER OF AGREEMENT
                              Date: January 2, 2002

Section 1. Services to be Rendered. The purpose of this letter (the "Agreement")
           -----------------------
is to set forth the terms and conditions on which The Investor Relations Group,
Inc. (IRG) agrees to provide One Voice Technologies, Inc. (the "Company")
investor relations services. These services may include, but are not limited to:
overall management of the corporate communications program; designing a
corporate fact sheet that can readily be mass produced for distribution to
brokers, analysts, and other industry personnel; securing one-on-one and group
appointments with industry professionals for presentations by, for, and about
Company management; targeted mailings; assistance with compiling promotional
materials; writing and editing news releases; advice on packaging the Company
story; and, daily update reports.

Section 2. Fees. The Company shall pay to IRG for its services hereunder
           ----
including investor relations and public relations services a fee of US $8,000
per month beginning January 2, 2002. Additionally, for this Agreement, the
Company agrees to deliver to IRG 150,000 warrants, priced at US $0.69 (the
current market price) per share with a five-year expiration. Such warrants shall
be granted and delivered no later than five (5) business days after the
execution of this Agreement and shall vest upon signing. The Company agrees to
fully register resale of the all of the above mentioned shares in conjunction
with the first appropriate registration executed. All shares and warrants shall
be issued in the name of Dian Griesel and shall be assignable to other IRG
employees.

     Fees are payable on or before the 1st day after the beginning of each month
which occurs during the Term of this Agreement. Unless other arrangements have
been made, lack of payment for services rendered by the 15/th/ of the month will
be considered default of this Agreement, and IRG shall be entitled to cease all
services on behalf of the Company until such time complete restitution is made
and IRG will be entitled to immediately collect the entire remaining balance due
under the terms of this Agreement.

     In the event, IRG is asked to serve as "finder" for a private placement,
bridge loan, or secondary or assists the Company in obtaining any other form of
private financing, IRG shall be entitled to additional compensation which shall
be calculated pursuant to the standard industry Lehman 5,4,3,2,1 formula.

     The Lehman formula shall be defined to mean that IRG shall receive five
percent (5%) of the first million dollars raised; four percent (4%) of the
second million dollars raised; three percent (3%) of the third million dollars
raised; two percent (2%) of the fourth million dollars raised; and one percent
(1%) of each subsequent million dollars raised.

Section 3. Expenses. In addition to all other fees payable to IRG hereunder, the
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Company hereby agrees to reimburse IRG for all reasonable out-of-pocket expenses
incurred in connection with the performance of services hereunder. These
out-of-pocket expenses shall include, but are not limited to: telephone,
photocopying, postage, messenger service, clipping service, maintaining mailing
lists, information retrieval service, wire services, monitoring advisory
service, all production costs for press releases including paper, envelopes,
folding, insertion and delivery to the post office, all reasonable travel and
entertainment expenses, and all reasonable meeting expenses including rental of
audio/visual equipment. No individual expenses over US $500 will be expended
without first notifying the Company. The Company agrees to remit upon the
signing of this Agreement a check for US $3,500 to be placed on deposit with IRG
and credited to the Company against expenses incurred, on a permanent basis,
throughout the program. From time to time, the Company will replenish the
expense account as necessary to maintain a balance of US $3,500. The balance of
said deposit is fully refundable should the program terminate. A running invoice
will be maintained of all expenses incurred and will be submitted to the Company
each month.

Section 4. Indemnification. The Company and IRG agree to defend, indemnify and
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hold each other, their affiliates, stockholders, directors officers, agents,
employees, successors and assigns (each an "Indemnified

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Person") harmless from and against any and all liabilities, obligations, losses,
damages, penalties, actions, judgements, suits, costs, expenses and
disbursements of any kind whatsoever (including, without limitation, reasonable
attorneys' fees) arising solely form the Company's or IRG's breach of their
obligations, warranties and representations under this Agreement. It is
recognized and agreed by IRG and the Company that neither party shall have any
liability hereunder to any Indemnified Person arising from the other party's
intentional negligence or willful misconduct. It is further agreed that the
foregoing indemnity shall be in addition to any rights that either party may
have at common law or otherwise, including, but not limited to, any right to
contribution.

Section 5. Term of Agreement and Guarantee of Satisfaction. (a) The term
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("Term") of this Agreement is for a period of twelve (12) months beginning
January 2, 2002 and may be extended upon written consent of both parties. (b)
The Company may terminate this Agreement at any time with or without cause. Any
fees accrued to IRG prior to cancellation will be payable immediately. (c) IRG
may terminate this Agreement at any time with or without cause. The obligations
of the Company under Sections 4 and 6 shall survive termination or breach of
this Agreement, with or without cause, by either party.

Section 6. Severability. In case any provision of this Agreement shall be
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invalid, illegal, or unenforceable, the validity, legality and enforceability of
the remaining provisions shall not be affected or impaired thereby.

Section 7. Consent to Jurisdiction. This Agreement shall be governed and
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construed in accordance with the laws of the State of New York, and the parties
hereby consent to the exclusive jurisdiction of the State and Federal Courts,
located within the City, County and State of New York to resolve any disputes
arising under this Agreement.

Section 8. Other Services. If the Company desires additional services not
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included in this Agreement, any such additional services shall be covered by a
separate agreement between the parties hereto.

     Please evidence your acceptance of the provisions of this letter by signing
the copy of this letter enclosed herewith and returning it to The Investor
Relations Group Inc., 50 Pine Street, 6th Floor, New York, NY 10005, Attention:
Dian Griesel, Ph.D., President & CEO.

                                Very truly yours,

                       ____________________________________________
                                Dian Griesel
                                Founder & President
                                The Investor Relations Group, Inc.

ACCEPTED AND AGREED
AS OF THE DATE FIRST ABOVE WRITTEN:

__________________________________

Dean Weber, CEO
One Voice Technologies, Inc.<PAGE>

                                                                  EXHIBIT 10.20
                                FIRST AMENDMENT
                                       TO
                             STOCKHOLDERS AGREEMENT

          This First Amendment to Stockholders Agreement (this "Amendment"),
dated as of January 21, 2002, hereby amends that certain Stockholders' Agreement
(the "Existing Agreement"), dated July 8, 1998, by and among Century Maintenance
Supply, Inc., a Delaware corporation (the "Company"), FS Equity Partners IV,
L.P., a Delaware limited partnership ("FSEP IV" or the "FS Stockholder"),
William C. Johnson ("Johnson"), The Parthenon Group, Inc., a Delaware
corporation ("Parthenon" and collectively with Johnson, the "Additional
Stockholders"), Dennis C. Bearden ("Bearden") and Century Airconditioning
Supply, Inc., a Texas corporation ("CAC", and collectively with Bearden, the
"Existing Stockholders"). Capitalized terms not otherwise defined herein shall
have the meaning ascribed to such terms in the Existing Agreement.

                                R E C I T A L S
                                - - - - - - - -

          WHEREAS, the Company, FSEP IV, Johnson, Parthenon and the Existing
Stockholders, are parties to the Existing Agreement.

          WHEREAS, Section 11 of the Existing Agreement permits the Existing
Agreement to be amended solely by FSEP IV so long as such amendment does not
prejudice the existing rights of the Existing Stockholders, Johnson or
Parthenon.

          WHEREAS, FSEP IV, pursuant to Section 11 of the Existing Agreement,
desires to add Joseph Semmer ("Semmer") as a party to the Existing Agreement on
terms and conditions which do not prejudice the rights of the Existing
Stockholders, Johnson or Parthenon.

          WHEREAS, Semmer, in connection with his acquisition of Company common
stock and appointment as the Company's Chief Executive Officer, has agreed to
become a party to the Existing Agreement.

          NOW, THEREFORE, Semmer hereby agrees to be bound by the terms and
conditions of the Existing Agreement, as amended by this Amendment, and FSEP IV
hereby consents and agrees to amend the Existing Agreement as follows:

          1.   Joseph Semmer.  The Existing Agreement is hereby amended by
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adding the following definition after the definition of "Securities Act" and
before the definition of "Stockholders":

          "Semmer:  Joseph Semmer."
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          2.   Additional Stockholders.  The definition of "Additional
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Stockholders" in the Existing Agreement is hereby amended to read in its
entirety as follows:

          "Johnson, Parthenon and Semmer."

          3.   Permitted Transferee.  The definition of "Permitted Transferee"
               --------------------
in the Existing Agreement is hereby amended by removing clause (iii) and
substituting in its place a new clause (iii) as follows:

          "(iii) with respect to Bearden, Johnson and Semmer, a family
          trust, limited partnership, corporation or other entity
          established by Bearden, Johnson or Semmer, as applicable,
          all of the beneficiaries or owners of which are immediate
          family members of Bearden, Johnson or Semmer, as applicable,
          (provided, that in the case of any entity established by
          Bearden, Johnson or Semmer, as applicable, pursuant to this
          subparagraph (iii) other than such family trust, the owners
          thereof shall specifically agree that, notwithstanding
          anything contained in this Agreement to the contrary, such
          owners shall not further Transfer their ownership interests
          in such entity to any other Person), and"

          4.   Rights Upon Issuance of Additional Securities.  Section 2 of the
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Existing Agreement is hereby amended and restated to read as follows:

          "The Company hereby grants to each Initial Stockholder,
          Johnson and Semmer (Johnson and Semmer collectively with the
          Initial Stockholders, the "Notified Stockholders") the
          following rights with respect to any and all proposed
          issuances or sales of Additional Securities by the Company:"

          5.   Termination and Assignment.  Section 2.5 of the Existing
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Agreement is hereby amended by removing clause (iii) and substituting in its
place a new clause (iii) as follows:

          "(iii) with respect to Johnson and Semmer, at such time that
          the FS Stockholder's rights under this Section 2.5 shall
          have terminated pursuant to subparagraph (ii) hereof."

          6.   Transfer Restrictions Binding Stockholders.  The final sentence
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of Section 5.1(a) of the Existing Agreement is hereby amended and restated to
read as follows:

          "The Transfer of Securities from any Stockholder to a
          Permitted Transferee may be made without complying with
          Section 5.2; provided, that each of such transferees
          executes a written undertaking to be and becomes bound by
          this Agreement in the
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          same manner and to the same extent as such Stockholder and,
          in the case of Permitted Transferees of the Existing
          Stockholders, Johnson, Parthenon or Semmer, respectively,
          (i) executes an irrevocable power of attorney appointing
          Bearden, Johnson, Richard Crosier and Steven Smith, or
          Semmer, respectively (or an individual designated by such
          individuals, as applicable, if such individual is unable to
          act due to death or disability) as such transferee's
          attorney-in-fact with sole irrevocable power and authority
          to make all decisions on behalf of and take all actions
          required to be taken by such transferee in connection with
          this Agreement, including (without limitation) any required
          sale of Securities pursuant to Section 4 hereof, and (ii) if
          requested by the FS Stockholder, delivers an opinion of
          legal counsel reasonably satisfactory to the FS Stockholder
          that such undertaking is binding and enforceable."

          7.   Notices.  Section 13 of the Existing Agreement is hereby amended
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by adding the following immediately after the "Facsimile:  (617) 526-5000":

          "If to Semmer:

               Joseph Semmer
               ____________________
               ____________________
               ____________________
               Telecopy No.:        "
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          IN WITNESS WHEREOF, the undersigned have executed this Amendment as of
the date first set forth above.

                         FS EQUITY PARTNERS IV, L.P.
                         a Delaware limited partnership

                         By:  FS Capital Partners, LLC
                         Its: General Partner

                              By: /s/ J. Frederick Simmons
                                  ----------------------------------
                                    J. Frederick Simmons
                                    Managing Member

                         JOSEPH SEMMER

                         /s/ Joseph Semmer
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