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Silicon Valley Bank

                          Amendment to Loan Documents

Borrower: Telesciences Inc. (formerly Axiom Inc.)

Date:     June 18, 1999

     THIS AMENDMENT TO LOAN DOCUMENTS is entered into between SILICON VALLEY
BANK ("Silicon") and the borrower named above ("BOrrower").

     The Parties agree to amend the Loan and Security Agreement between them,
dated December 7, 1998 (as previously amended, if at all, the "Loan Agreement"),
as follows, effective as of the date hereof. (Capitalized terms used but not
defined in this Amendment, shall have the meanings set forth in the Loan
Agreement.)

     1.   Overadvance. Borrower has requested that Silicon make Loans in an
amount which will cause the aggregate outstanding Loans to exceed the
limitations set forth in the Loan Agreement by up to $3,000,000 (the
"Overadvance").

     Silicon agrees to make the Overadvance to Borrower, and, on consideration
thereof, Borrower agrees: (i) to secure the Overadvance by providing Silicon
with a letter of credit in the amount of the Overadvance , issued by a bank
acceptable to Silicon, and containing terms and conditions acceptable to
Silicon; (ii) to repay the Overadvance in full or on before the date which is
thirty days from the Maturity Date; and (iii) not to permit the Overadvance to
exceed $3,000,000 at any time outstanding.

     Borrower understands that, by making the Overadvance, Silicon is not
waiving any Event of Default which may result from any overadvance which may
occur in the future, or any other Event of Default.

     2.   Amendment of Financial Covenant. Section 5 of the Schedule is hereby
amended to read as follows:

     "5.  Financial
         Covenants
         (Section 5.1):  Borrower shall comply with the following covenant.
                         Compliance shall be determined as of the end of each
                         quarter.

         Minimum Tangible
         Net Worth:      Borrower shall maintain a Tangible Net Worth of not
                         less than $8,200,000, plus 75% of the sum of (i) the
                         Borrower's net income earned subsequent to the date of
                         the Loan Agreement, plus (ii) the proceeds of any
                         issuance(s) of equity or subordinated debt by the
                         Borrower subsequent to the date of the Loan Agreement.

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             Silicon Valley Bank                  Amendment to Loan Documents
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        Definitions.          For purposes of the foregoing financial covenant,
                              the following terms shall have the following
                              meanings:

                              "Tangible Net Worth" shall mean the excess of
                              total assets over total liabilities, determined in
                              accordance with generally accepted accounting
                              principles, with the following adjustments:

                                   (A) there shall be excluded from assets: (i)
                                   notes, accounts receivable and other
                                   obligations owing to the Borrower from its
                                   officers or other Affiliates, and (ii) all
                                   assets which would be classified as
                                   intangible assets, under generally accepted
                                   accounting principles, including without
                                   limitation goodwill, licenses, parents,
                                   trademarks, trade names, copyrights,
                                   capitalized software and organizational
                                   costs, licenses and franchises

                                   (B) there shall be excluded from liabilities:
                                   all indebtedness which is subordinated to the
                                   Obligations under a subordination agreement
                                   in form specified by Silicon or by language
                                   in the instrument evidencing the indebtedness
                                   which is acceptable to Silicon in its
                                   discretion.

                              "Assets" and "liabilities" shall have the meanings
                              ascribed thereto by generally accepted accounting
                              principles."

     3.   Representations True. Borrower represents and warrants to Silicon that
all representations and warranties set forth in the Loan Agreement, as amended
hereby, are true and correct.

     4.   General Provisions. This Amendment, the Loan Agreement, any prior
written amendments to the Loan Agreement signed by Silicon and Borrower, and the
other written documents and agreements between Silicon and Borrower set forth in
full all of the representations and agreements of the parties with respect to
the subject matter hereof and supersede all prior discussions, representations,
agreements and understandings between the parties with respect to the subject
hereof. Except as herein expressly amended, all of the terms and provisions of
the Loan Agreement, and all other documents and agreements between Silicon and
Borrower shall continue in full force and effect and the same are hereby
ratified and confirmed.

  Borrower:                                  Silicon:

  TELESCIENCES, INC.                         SILICON VALLEY BANK

  By /s/ Andrew P. Maunder                   By /s/ Peter Bendoris
    --------------------------------           ---------------------------------
      President or Vice President            Title /s/ Assistant Vice President
                                                  ------------------------------

  By /s/ Frances Penfold
    --------------------------------
     Secretary or Ass't Secretary

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