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                                                                   Exhibit 10.20


                   AMENDMENTS TO THE 1998 INVESTMENT AGREEMENT


         (i) Paragraph (a) of the penultimate recital to the 1998 Investment
Agreement shall be restated in its entirety as follows as follows:

                           (a) Purchaser wishes to purchase from the Company,
                  and the Company wishes to sell to Purchaser, shares of Common
                  Stock and warrants having the terms and conditions set forth
                  in Exhibit 1 (as such warrants are amended from time to time,
                  whether pursuant to the Investment Agreement, dated as of
                  March 30, 1999, between the Company and Purchaser (the "1999
                  Investment Agreement") or otherwise, the "Special Warrants")
                  entitling the holder thereof to purchase shares of Common
                  Stock together representing 24.9% of the shares of Common
                  Stock as of the Closing Date (as herein defined) that would be
                  outstanding after giving effect to the issuance of such shares
                  (and assuming the conversion into Common Stock of all of the
                  Company's issued and outstanding 5 1/2% Convertible
                  Subordinated Notes Due 2001 issued pursuant to an Indenture,
                  dated as of February 7, 1996, between the Company and State
                  Street Bank and Trust Company (the "2001 Notes") that are
                  outstanding on the Closing Date, and after giving effect to
                  the issuance of any Contingent Stock (as defined herein)), and
                  warrants entitling the holder thereof to purchase one share of
                  Common Stock for each share and Special Warrant so purchased
                  on the terms and subject to the conditions set forth in
                  Exhibit 2 (as such warrants are amended from time to time,
                  whether pursuant to the 1999 Investment Agreement or
                  otherwise, the "Warrants"), and

         (ii) Paragraph (b) of Section 4.01 of the 1998 Investment Agreement
shall be restated in its entirety as follows:

                  (b) Purchaser shall be entitled to nominate three directors
for election, PROVIDED:

                           (i) if the total number of shares of Common Stock
                  represented by the Shares, the Special Warrants and the
                  Warrants ("Purchaser's Total Securities") declines by more
                  than 33_% but less than 66_% from Purchaser's Total Securities
                  at Closing by reason of sales or other dispositions of Common
                  Stock, Warrants or Special Warrants by Purchaser, Purchaser
                  shall have the right to nominate two directors;

                           (ii) if Purchaser's Total Securities declines by 66_%
                  or more from Purchaser's Total Securities at Closing, but
                  Purchaser's Percentage Interest remains at least 5% of the
                  outstanding Voting Securities, by reason of


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                  sales or other dispositions of Common Stock, Warrants or
                  Special Warrants by Purchaser, Purchaser shall have the right
                  to nominate one director;

                           (iii) for the purpose of calculating Purchaser's
                  Total Securities as of any time after the closing under the
                  1999 Investment Agreement (but not for the purpose of
                  calculating Purchaser's Total Securities at Closing), each
                  Preferred Share owned by Purchaser shall be treated as if it
                  were 100 Shares.

                           (iv) in the event that the size of the Board of
                  Directors shall be increased, Purchaser shall have the right
                  to at least proportionate representation on the Board
                  following such increase based on the composition of the Board
                  as between Investor Directors and Non-Investor Directors
                  immediately prior to such increase; PROVIDED that in no event
                  shall the Board consist of more than 12 directors; and

                           (v) if the chief executive officer of the Company is
                  not then a member of the Board of Directors or a nominee for
                  membership thereon, the Purchaser shall be entitled to approve
                  an additional nominee to the Board of Directors.

         (iii) Paragraph (a) of Section 6.01 of the 1998 Investment Agreement
shall be restated in its entirety as follows:

                           (a) Except as permitted by Section 6.01(b) or
                  6.01(c), neither Purchaser nor its Affiliates will directly or
                  indirectly acquire any securities (including by exercise of
                  the Warrants or Special Warrants) or take any other action
                  that would cause (i) the percentage of the Total Voting Power
                  represented by the aggregate voting power of all Voting
                  Securities then held by Purchaser to equal or exceed 26.7% or
                  (ii) the aggregate voting power of all Equity Securities then
                  held by Purchaser (on an as converted basis) to equal or
                  exceed 50%.

         (iv) Paragraph (c) of Section 6.01 of the 1998 Investment Agreement
shall be restated in its entirety as follows:

                           (c) This Section 6.01 shall terminate and be of no
                  further force or effect on the earliest to occur of (i) the
                  fifth anniversary of the Closing, (ii) the date on which the
                  percentage of the Total Voting Power represented by the
                  aggregate voting power of all Voting Securities then owned by
                  Purchaser (other than any Voting Securities acquired in
                  violation of this Agreement) is greater than 50%, and (iii)
                  the first public disclosure of a Third-Party Bid (provided,
                  however, that if such Third-Party Bid is




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                  thereafter abandoned, terminated or withdrawn, the provisions
                  of this Section 6.01 shall be reinstated, although any action
                  taken or agreement or arrangement entered into by Purchaser
                  after such first public disclosure and prior to such
                  reinstatement (or the consummation of any such action,
                  agreement or arrangement, whether before or, unless such
                  action, agreement or arrangement shall be a tender offer or
                  other public offer with respect to the Company, after such
                  reinstatement) shall not be deemed to breach this Section 6.01
                  as a result of such reinstatement).

         (v) The first paragraph of Section 6.02 of the 1998 Investment
Agreement shall be restated in its entirety as follows:

                           SECTION 6.02 ADDITIONAL LIMITATIONS. (a) Except as
                  permitted by Section 6.02(b), during the five-year period
                  beginning on the date of this Agreement, Purchaser shall not,
                  and shall not permit its Affiliates to:

         (vi) Section 6.02 of the 1998 Investment Agreement shall be amended by
adding a section (b) as follows:

                           (b) The limitations set forth in Section 6.02 (a)
                  hereof shall not apply (x) in connection with a Buyout
                  Transaction that is not solicited or proposed by Purchaser or
                  its Affiliates, (y) following the first public disclosure of a
                  Third-Party Bid (provided, however, that if such Third-Party
                  Bid is thereafter abandoned, terminated or withdrawn, the
                  provisions of Section 6.02 (a) hereof shall be reinstated,
                  although any action taken or agreement or arrangement entered
                  into by Purchaser after such first public disclosure and prior
                  to such reinstatement (or the consummation of any such action,
                  agreement or arrangement, whether before or, unless such
                  action, agreement or arrangement shall be a tender offer or
                  other public offer with respect to the Company, after such
                  reinstatement) shall not be deemed to breach the provisions of
                  Section 6.02 (a) hereof as a result of such reinstatement), or
                  (z) as specifically approved by a majority of the Non-Investor
                  Directors

         (vii) Paragraphs (c) and (d) of Section 7.01 of the 1998 Investment
Agreement shall be restated in their entirety as follows:

                           (c) The provisions of clauses (a) and (b) of this
                  Article VII shall terminate and be of no further force or
                  effect on the earliest to occur of (i) the fifth anniversary
                  of the Closing, (ii) the date on which the percentage of the
                  Total Voting Power represented by the aggregate voting power
                  of all Voting Securities then owned by Purchaser (other than
                  any Voting Securities acquired in violation of this Agreement)
                  is greater than 50%, and (iii) the first public disclosure of
                  a Third-Party Bid (provided,



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                  however, that if such Third-Party Bid is thereafter abandoned,
                  terminated or withdrawn, the provisions of clauses (a) and (b)
                  of this Article VII shall be reinstated, although any action
                  taken or agreement or arrangement entered into by Purchaser
                  after such first public disclosure and prior to such
                  reinstatement (or the consummation of any such action,
                  agreement or arrangement, whether before or, unless such
                  action, agreement or arrangement shall be a tender offer or
                  other public offer with respect to the Company, after such
                  reinstatement) shall not be deemed to breach the provisions of
                  clauses (a) and (b) of this Article VII as a result of such
                  reinstatement).

                           (d) Prior to the seventh anniversary of the Closing,
                  the Purchaser will not, directly or otherwise dispose of
                  Shares representing 15% or more of the then outstanding Common
                  Stock, to any Person or group (within the meaning of Section
                  13(d)(3) of the Exchange Act) without first offering the
                  Company the right to make an offer to purchase the Shares
                  proposed to be so sold, transferred or otherwise disposed of.
                  The provisions of the previous sentence shall terminate and be
                  of no effect on the earlier to occur of (i) the date on which
                  the percentage of the Total Voting Power represented by the
                  aggregate voting power of all Voting Securities then owned by
                  Purchaser (other than any Voting Securities acquired in
                  violation of this Agreement) is greater than 50%, and (ii) the
                  first public disclosure of a Third Party Bid (provided,
                  however, that if such Third-Party Bid is thereafter abandoned,
                  terminated or withdrawn, the provisions of this Section 7.01
                  (d) shall be reinstated, although any action taken or
                  agreement or arrangement entered into by Purchaser after such
                  first public disclosure and prior to such reinstatement (or
                  the consummation of any such action, agreement or arrangement,
                  whether before or, unless such action, agreement or
                  arrangement shall be a tender offer or other public offer with
                  respect to the Company, after such reinstatement) shall not be
                  deemed to breach this Section 7.01 (d) as a result of such
                  reinstatement).

         (viii) Section 8.10 of the 1998 Investment Agreement shall be restated
in its entirety as follows:


                           Section 8.10 TAX STANDSTILL. Except as permitted by
                  Section 6.01(b) or 6.01(c) and except for acquisitions of
                  Securities from the Company, during the period ending two
                  years after the date of the Distributions, (i) Purchaser shall
                  not acquire any Securities or take any other action that would
                  cause Purchaser's Percentage Interest to equal or exceed 50%,
                  (ii) none of Purchaser, the Fund or CD&R shall act in concert
                  with any other Person to acquire any Securities if aggregating
                  such



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                  acquisition with the Purchaser's holdings would cause the
                  Purchaser's Percentage Interest to equal or exceed 50%, and
                  (iii) none of Purchaser, the Fund or CD&R shall solicit the
                  acquisition of any Securities, PROVIDED that the provision by
                  the Fund to its limited partners of customary reports and
                  information, and customary communication with such limited
                  partners on behalf of the Fund, with respect to the Fund's
                  investment in the Company that, in either case, do not
                  recommend any such acquisition, shall not be treated as a
                  solicitation by the Purchaser within the meaning of this
                  clause (iii). The limitations contained in this Section 8.10
                  shall terminate upon the first public disclosure of a
                  Third-Party Bid (provided, however, that if such Third-Party
                  Bid is thereafter abandoned, terminated or withdrawn, the
                  provisions of this Section 8.10 shall be reinstated, although
                  any action taken or agreement or arrangement entered into by
                  Purchaser after such first public disclosure and prior to such
                  reinstatement (or the consummation of any such action,
                  agreement or arrangement, whether before or, unless such
                  action, agreement or arrangement shall be a tender offer or
                  other public offer with respect to the Company, after such
                  reinstatement) shall not be deemed to breach this Section 8.10
                  as a result of such reinstatement).



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         (ix) Section 12.02 of the 1998 Investment Agreement shall be amended by
inserting, immediately following the definition of "Pre-Distribution
Transactions", a new definition as follows:

                           "PREFERRED SHARES" means the shares of Series A
                  Non-Voting Participating Convertible Preferred Stock of the
                  Company, par value $.001 per share, purchased by Purchaser
                  pursuant to an Investment Agreement, dated as of March 30,
                  1999, between the Company and Purchaser.

         (x) Section 12.02 of the 1998 Investment Agreement shall be amended by
restating the definition of "Pro Rata Share", as follows:

                           "PRO RATA SHARE" means the fraction of an entire
                  issuance of New Securities, the numerator of which shall be
                  the sum of (a) the number of shares of Common Stock owned or
                  receivable upon exercise of the Warrants and the Special
                  Warrants by Purchaser and its Affiliates (other than the
                  Company and its Subsidiaries) immediately prior to such
                  issuance of such New Securities and (b) the number of shares
                  of Common Stock into which the Preferred Shares owned by
                  Purchaser and its Affiliates are convertible, and the
                  denominator of which shall be the sum of (x) the aggregate
                  number of shares of Common Stock outstanding immediately prior
                  to such issuance of such New Securities and receivable upon
                  exercise of the Warrants and the Special Warrants and (y) the
                  number of shares of Common Stock into which such Preferred
                  Shares are convertible.

         (xi) Section 12.02 of the 1998 Investment Agreement shall be amended by
inserting, immediately following the definition of "Termination Fee", a new
definition as follows:

                           "THIRD-PARTY BID" means an unsolicited bona fide
                  tender offer or other public offer by a Person other than
                  Purchaser, an Affiliate thereof or the Company or any of its
                  Subsidiaries (a "THIRD PARTY") to purchase a number of shares
                  of Common Stock which, together with the shares of Common
                  Stock Beneficially Owned by such Third Party, would result in
                  the Third Party being the Beneficial Owner of 25% or more of
                  the shares of Common Stock outstanding.




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