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                                                                  EXHIBIT 10.4.9

FOURTH AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT

       This Fourth Amendment to Amended and Restated Credit Agreement (this
"Agreement") is made as of July 15, 1998 by and between BITSTREAM INC., a
Delaware corporation with a place of business at 215 First Street, Cambridge,
Massachusetts 02142 (the "Borrower") and BANKBOSTON, N.A., successor by merger
with BayBank, N.A., formerly known as BayBank, with an address at 100 Federal
Street, Boston, Massachusetts 02110 (the "Bank").

       WHEREAS, the Bank and the Borrower have entered into a loan arrangement
as of July 14, 1995, evidenced by, among other documents (the "Loan Documents"),
a certain Credit Agreement dated as of July 14, 1995 by and between Borrower and
Bank, as amended and restated by a certain Amended and Restated Credit Agreement
dated March 18, 1996, as amended by a certain First Amendment to Amended and
Restated Credit Agreement dated June 28, 1996, as amended by a certain Second
Amendment to Amended and Restated Credit Agreement dated August 29, 1997, as
amended by a certain Third Amendment to Amended and Restated Credit Agreement
dated March 20, 1998 (as amended, the "Credit Agreement"). Terms used but not
defined herein are used with the meanings ascribed to them in the Credit
Agreement.

       WHEREAS, the Borrower has requested, and the Bank has agreed, to amend
certain terms of the Loan Documents, as more particularly set forth herein.

       NOW THEREFORE, for good and valuable consideration, the receipt, adequacy
and sufficiency of which is hereby acknowledged, the parties hereto agree,
effective as of the date hereof, as follows:

            The Credit Agreement shall be amended by deleting the following text
      appearing as Section 9.1 on Page 30 thereof:

                  "9.1 PROFITABILITY. The Borrower shall not incur an operating
            loss of greater than: (i) $1,000,000.00 for fiscal year 1997,
            exclusive of acquisition and non-recurring charges incurred during
            the second quarter of 1997, and (ii) $500,000.00 for the first two
            quarters of fiscal 1998."

      and substituting in lieu thereof the following text:

                  "9.1 PROFITABILITY. The Borrower shall not incur an operating
            loss of greater than: (i) $1,000,000.00 for fiscal year 1997,
            exclusive of acquisition and non-recurring charges incurred during
            the second quarter of 1997, and (ii) $2,800,000.00 for the first two
            quarters of fiscal 1998."

            CONDITIONS. The effectiveness of this Agreement shall be subject to
      the compliance by the Borrower with its representations, warranties,
      covenants and agreements contained herein and in the Loan Documents after
      giving effect to the amendments thereto contemplated hereby, and to the
      prior satisfaction of the following further conditions:

                  CORPORATE DUE DILIGENCE. The Borrower shall deliver to the
            Bank evidence that all necessary corporate actions in connection
            with the making of this Agreement and the transactions contemplated
            hereby and thereby have been taken by the Borrower.

                  BANK'S EXPENSES. The Borrower shall pay all of the Bank's
            reasonable out-of-pocket expenses, including the attorneys' fees 


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            and disbursements of the Bank's counsel, Riemer & Braunstein, in
            connection with this Agreement, the transactions contemplated hereby
            and the matters referred to herein and the Loan Documents.

                  GENERAL. All instruments and legal and corporate proceedings
            in connection with this Agreement and the transactions contemplated
            hereby shall be satisfactory in form and substance to the Bank and
            its counsel, and the Bank and its counsel shall have received copies
            of all documents, including records of corporate authority, which
            the Bank and its counsel may have requested in connection therewith.

            REPRESENTATIONS  AND  WARRANTIES.  The Borrower  hereby  represent
      and warrants that:

                  AUTHORITY.  The Borrower  has taken all action  necessary to
            enter  into this  Agreement  and all  agreements  and  instruments
            executed by the Borrower in connection herewith.

                  INCORPORATION OF REPRESENTATIONS AND WARRANTIES. The
            representations and warranties set forth in each of the Loan
            Documents, after giving effect to the within amendments, are true
            and correct on and as of the date hereof.

                  NO  DEFAULT,  ETC.  No breach of any of the Loan  Documents,
            as amended by this Amendment, exists on the date hereof.

            COVENANTS AND AGREEMENTS. The Borrower hereby reaffirms each of the
      covenants and agreements of the Borrower set forth in each of the Loan
      Documents. As hereby amended, the Loan Documents are hereby ratified and
      confirmed in all respects.

            MISCELLANEOUS. The invalidity or uneforceability of any term or
      provision hereof shall not affect the validity or enforceability of any
      other term or provision hereof. The headings in this Agreement are for
      convenience of reference only and shall not alter or otherwise affect the
      meaning hereof.

      This Agreement may be executed in any number of counterparts which
together shall constitute one instrument and shall be governed by and construed
in accordance with the laws (other than the conflict of law rules) of The
Commonwealth of Massachusetts and shall bind and inure to the benefit of the
parties hereto and their respective successors and assigns.



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      Executed as a sealed instrument as of the day and year first written
above.

WITNESS:                         BITSTREAM INC.


/s/ Paul Trevithick              By: /s/ Anna Chagnon
    ----------------                 ----------------
                                 Name: Anna Chagnon
                                  

                                 Title: Vice President, Finance And
                                        Administration


WITNESS:                         BANKBOSTON, N.A.


                                 By:
----------------------              ---------------------------------
                                 Name:
                                      -------------------------------
                                 Title:
                                       ------------------------------



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