Exhibit 10.8
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THIS  SUPPLEMENTAL  DEED OF  GUARANTEE  is made this 17th day of January 2001 by
GUILDSOFT LIMITED a company registered under the laws of England and Wales under
company  number  02567351  with its  registered  office at Unit A, The  Software
Centre,  East Way, Lee Mill Industrial  Estate,  Ivybridge,  Devon PL21 9PE (the
"Guarantor") in favour of SILICON VALLEY BANK a California  chartered bank, with
its principal  place of business at 3003 Tasman Drive,  Santa Clara,  California
95054 USA (the "Bank")

WHEREAS:

(A)      This Deed is supplemental to the Deed of Guarantee dated 27 December
         1999 and made between the same parties as this Deed (the "Principal
         Deed")

(B)      At the  request of (inter  alia) the  Guarantor  the Bank has agreed to
         vary the terms of the Loan  Agreements  (as  defined  in the  Principal
         Deed) and the  Guarantor  has agreed to vary the terms of the Principal
         Deed in manner hereafter appearing

WITNESSES as follows:

1.       INTERPRETATION

1.1      In this Deed words and expressions defined in the Principal Deed shall
         have the same meanings herein.

1.2      "Effective Date" means 29 December 2000.

2.       AMENDMENT

2.1      As from the Effective Date the Principal Deed shall be amended by the
         deletion of Clause 1(i) and substitution of the following:-

         "(i)     the  expression  the "Loan  Agreements"  means the Amended and
                  Restated Loan and Security  Agreement dated 16 March 1999 made
                  between the Bank and the Principal  and Personics  Corporation
                  as amended by the Loan  Modification  Agreement  dated of even
                  date herewith and made between  Datawatch  Corporation and the
                  Bank and the Export-Import Loan and Security Agreement of even
                  date herewith made between (inter alia) the Bank and Datawatch
                  Corporation  as each of them may be  amended,  renewed  and/or
                  restated from time to time."

2.2      Save as amended by Clause 2.1 above, all the terms of the Principal
         Deed shall remain in full force and effect.



3.       MISCELLANEOUS

Where the  context  admits  the  provisions  of Clause 1 of the  Principal  Deed
(Interpretation)  and the provisions of Clause 22 of the Principal Deed (Law and
Jurisdiction) shall apply (mutatis mutandis) to this Deed.

IN WITNESS  whereof this Deed has been  executed as a deed and  delivered by the
parties hereto on the day and year first before written.


EXECUTED AND DELIVERED as a Deed by
GUILDSOFT LIMITED acting by:-


 /s/  Bruce R. Gardner
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Director

 /s/  John F. Cave
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Director/Secretary



EXECUTED AND DELIVERED as a Deed by
SILICON VALLEY BANK by:-


 /s/  Maggie Garcia                                        .
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A person authorised under the laws of
California to execute and deliver a
document as a deed