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                                                                    Exhibit 4.8

                 AMENDMENTS TO THE REGISTRATION RIGHTS AGREEMENT

      (i) Section 1(a) of the Registration Rights Agreement shall be amended by
adding a new paragraph, immediately following the first paragraph, as follows:

          The Company is also a party to an Investment Agreement, dated as of
          March 30, 1999, with the Purchaser (the "1999 INVESTMENT AGREEMENT"),
          pursuant to which the Company agreed, in exchange for consideration of
          $51 million in cash (I) to issue to Purchaser up to 73,350 newly
          issued shares of Series A Non-Voting Participating Convertible
          Preferred Stock, par value $.001 per share (the "PREFERRED SHARES"),
          of the Company having the terms set forth in Exhibit I of the 1999
          Investment Agreement, (II) to amend and restate the Warrants as set
          forth in Exhibit II of the 1999 Investment Agreement, and (III) to
          amend and restate the Special Warrants as set forth in Exhibit III of
          the 1999 Investment Agreement.

     (ii) Section 1(b) of the Registration Rights Agreement shall be restated in
its entirety as follows:

                    (b) This Agreement shall become effective with respect to
          any Registrable Securities upon the issuance or sale of Registrable
          Securities pursuant to the Investment Agreement or the 1999 Investment
          Agreement. This Agreement shall remain in effect upon the assignment
          or transfer of Registrable Securities by the Purchaser or a Holder to
          an Affiliate, a Distributee or other successors, assigns and
          transferees of Purchaser of such Holder pursuant to Section 4.4.

    (iii) Section 2 of the Registration Rights Agreement shall be amended by
restating the definition of "Registrable Securities" in its entirety as
follows:

               "REGISTRABLE SECURITIES" means (a) the Shares, (b) the Additional
          Shares, (c) the Warrant Shares, (d) the Warrants, (e) the Special
          Warrant Shares, (f) the Special Warrants, (g) the Preferred Shares,
          (h) the Conversion Shares and (i) any securities issued or issuable
          with respect to any Shares, Additional Shares, Warrants, Special
          Warrants, Preferred Shares or Conversion Shares referred to in the
          foregoing clauses (a) through (h), (i) upon any conversion or exchange
          thereof, (ii) by way of stock dividend or other distribution, stock
          split or reverse stock split or (iii) in connection with a combination
          of shares, recapitalization, merger, consolidation, exchange offer or
          other reorganization. As to any particular Registrable Securities,
          once issued such securities shall cease to be Registrable Securities
          when (A) a Registration Statement with respect to the sale of such
          securities shall have become effective under the Securities Act and
          such securities shall have been disposed of in accordance with such
          Registration Statement, (B) such securities shall have been
          distributed to the public in reliance upon Rule 144, (C) subject to
          the provi-


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          sions of Section 4.1(b)(ii), such securities shall have been
          otherwise transferred, new certificates for such securities not
          bearing a legend restricting further transfer shall have been
          delivered by the Company and subsequent disposition of such securities
          shall not require registration or qualification of such securities
          under the Securities Act or any similar state law then in force or (D)
          such securities shall have been acquired by the Company. In
          determining the number of Registrable Securities outstanding at any
          time or whether the Holders of the requisite number of Registrable
          Securities have taken any action hereunder and in calculating the
          number of Registrable Securities for all other purposes under this
          Agreement, each Warrant and Special Warrant shall be deemed to have
          been exercised (to the fullest extent then determinable) and each
          Preferred Share shall be deemed to have been converted and such
          calculation shall include the number of Warrant Shares and Special
          Warrant Shares then deliverable upon the exercise of such Warrant or
          Special Warrant and the number of Conversion Shares deliverable upon
          conversion of the Preferred Shares (to the fullest extent then
          determinable).

     (iv) Section 2 of the Registration Rights Agreement shall be amended by
inserting, immediately following the definition of "Contingent Stock", a new
definition as follows:

               "CONVERSION SHARES" means the shares of Common Stock issuable
          upon conversion of the Preferred Shares.

      (v) Section 2 of the Registration Rights Agreement shall be amended by
inserting, immediately following the definition of "Postponement Period", a new
definition as follows:

               "PREFERRED SHARES" is defined in Section 1(a).


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     (vi) Section 2 of the Registration Rights Agreement shall be amended by
restating the definition of "Special Warrants" as follows:

               "SPECIAL WARRANTS" means warrants entitling the holder thereof to
          purchase shares of Common Stock on the terms and subject to the
          conditions set forth in Exhibit 1 of the Investment Agreement, and any
          warrants of the Company received in exchange therefor, pursuant to the
          1999 Investment Agreement or otherwise.

    (vii) Section 2 of the Registration Rights Agreement shall be amended by
restating the definition of "Warrants" as follows:

               "WARRANTS" means warrants entitling the holder thereof to
          purchase one share of Common Stock for each Share and Special Warrant
          purchased by the Purchaser pursuant to the Investment Agreement, on
          the terms and subject to the conditions set forth in Exhibit 2
          thereof, and any warrants of the Company received in exchange
          therefor, pursuant to the 1999 Investment Agreement or otherwise.

   (viii) Paragraph (a) of Section 3.1 of the Registration Rights Agreement
shall be restated in its entirety as follows:

               (A) REQUESTS. Subject to the provisions of Section 3.6, at any
          time or from time to time as of the date hereof, Holders of not less
          than 25% of the then outstanding Registrable Securities shall have the
          right to make written requests that the Company effect up to six
          registrations under the Securities Act of all or part of the
          Registrable Securities of the Holders making such request, which
          requests shall specify the intended method of disposition thereof by
          such Holders, including whether the registration requested is for an
          underwritten offering. For a registration to be underwritten, a
          majority of the Holders requesting registration (as measured by
          ownership of Registrable Securities) must so request. The Company
          shall not be required to effect more than [six] registrations under
          this Section 3.1.

     (ix) Clause C of Section 3.1(f)(iii) of the Registration Rights Agreement
shall be restated in its entirety as follows:

               (C) third, to the extent that the number of shares registered
          pursuant to clauses (A) and (B) is less than the largest number that
          can be sold in an orderly manner in such offering within a price range
          acceptable to the selling Holders, the securities requested to be
          included by any other holders (if permitted by the Holders pursuant to
          Section 3.1(f)(ii)).


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