<PAGE>   1
                                                                   EXHIBIT 10.20

                     FOURTH AMENDMENT TO THE SECOND AMENDED
                             AND RESTATED CONTINGENT
                MULTICURRENCY NOTE PURCHASE COMMITMENT AGREEMENT


         THIS AMENDMENT (this "Amendment"), dated as of January 5, 2000, is made
to the Second Amended and Restated Contingent Multicurrency Note Purchase
Commitment Agreement, dated as of January 15, 1998 (as heretofore or hereafter
amended, modified or supplemented from time to time, the "Agreement"), between
STORAGE TECHNOLOGY CORPORATION ("Borrower") and BANK OF AMERICA, N.A. (formerly
Bank of America National Trust and Savings Association) ("BofA"). Capitalized
terms used but not otherwise defined herein shall have the meanings assigned to
such terms by the Agreement.

         WHEREAS, Borrower and BofA desire to amend and supplement the Agreement
as hereinafter set forth.

         NOW, THEREFORE, in consideration of the premises and the mutual
agreements herein contained, the parties hereto agree as follows:


                                    ARTICLE I
                             AMENDMENTS TO AGREEMENT

         Section 1.1 Amendment to Section 1.04. Section 1.04 of the Agreement is
hereby amended and restated to read in its entirety as follows:

                  "Section 1.04 Disbursement of Purchase Price into Collateral
         Account; Notice of Collateral Status and Excess Purchase Price Amounts.
         The Borrower will notify BofA in writing no later than 10:00 a.m. (San
         Francisco time) on each LIBOR Fixing Date (i) whether Borrower will be
         in Collateral Status or an Excess Purchase Price Amount will exist, in
         either case, on the Purchase Date immediately following such LIBOR
         Fixing Date, and (ii) if Borrower will be in Collateral Status or an
         Excess Purchase Price Amount will exist, in either case, on such
         Purchase Date, the amount to be deposited into the Collateral Account
         on such Purchase Date in order to enable the Borrower to meet its
         obligations under Section 6.01(h).".

         Section 1.2 Amendment to Definition of "Applicable Margin". Section
1.05(f) of the Agreement is hereby amended and restated to read in its entirety
as follows:



<PAGE>   2

         "(f) The "Applicable Margin" on each day during the Period to Maturity
of any Note shall be:

               (1) if on the Purchase Date of such Note Borrower is in
          Collateral Status, 0.350%,

               (2) if on the Purchase Date of such Note Borrower is not in
          Collateral Status and no Excess Purchase Price Amount exists, the
          Applicable Margin will be determined by BofA on such Purchase Date in
          accordance with the table set forth below. Such determination shall be
          based on the calculations of the ratio of (x) Consolidated Total Debt
          on the last day of the most recent Fiscal Quarter of the Borrower and
          its Subsidiaries for which a Compliance Certificate shall have been
          delivered pursuant to Section 6.01(g)(vii), as shown in such
          Compliance Certificate, to (y) the sum of EBITDA of the Borrower and
          its Subsidiaries for the period of four Fiscal Quarters ending on such
          last day, as shown in such Compliance Certificate.

<TABLE>
<CAPTION>

          Consolidated Total Debt
                to EBITDA
           (rolling four quarter)                                         Applicable Margin
           ----------------------                                         -----------------
<S>                                                                       <C>
           If Less than 1.50                                                    +2.000%

           If Less than 2.00 but greater than                                   +2.125%
             or equal to 1.50

           If Less than 2.50 but greater than                                   +2.250%
             or equal to 2.00

           If Greater than or equal to 2.50                                     +2.500%
</TABLE>

                  (iii) if on the Purchase Date of such Note Borrower is not in
         Collateral Status, but an Excess Purchase Price Amount exists, the
         Applicable Margin will be a percentage, calculated according to the
         following formula:


         Applicable Margin  =    EPPA * 0.350%      +        (APP - EPPA) * AM
                                 -------------               -----------------
                                      APP                            APP

         WHERE:

                  EPPA    =         the Excess Purchase Price Amount on such
                                    Purchase Date, provided, that, in the event
                                    the Borrower has not deposited, and for so
                                    long (but



<PAGE>   3

                                    only for so long) as Borrower has
                                    not deposited an amount equal to such Excess
                                    Purchase Price Amount into the Collateral
                                    Account on such Purchase Date in accordance
                                    with Section 6.01(h), "EPPA" on such
                                    Purchase Date shall be an amount equal to
                                    the amount on deposit in the Collateral
                                    Account on such Purchase Date;

                  APP     =         the aggregate of the Purchase Prices of
                                    all Notes which are outstanding or to be
                                    issued on such Purchase Date (after giving
                                    effect to any Notes which will be repaid on
                                    such Purchase Date); and

                  AM      =         the Applicable Margin that would have been
                                    in effect on such Purchase Date pursuant to
                                    Section 1.05(f)(ii) if the Excess Purchase
                                    Price Amount on such Purchase Date had not
                                    been greater than zero.

                  (iv) Except to the extent provided in the definition of "EPPA"
         above, the determination of the Applicable Margin for any Note for
         purposes of this Section 1.05(f) shall be made on the Purchase Date of
         such Note and such determination shall apply to each day during the
         Period to Maturity of such Note.".

         Section 1.3 Amendment to Definition of "Applicable Facility Fee Rate".
Section 3.01(b) of the Agreement is hereby amended and restated to read in its
entirety as follows:

         "(b)     The "Applicable Facility Fee Rate" shall be:

                  (i)  0.150% on any day when Borrower is in Collateral Status.

                  (ii) on any day when Borrower is not in Collateral Status and
         no Excess Purchase Price Amount exists, the Applicable Facility Fee
         Rate will be determined by BofA on such day in accordance with the
         table set forth below. Such determination shall be based on the
         calculations of (i) the ratio of (x) Consolidated Total Debt on the
         last day of the most recent Fiscal Quarter of the Borrower and its
         Subsidiaries for which a Compliance Certificate shall have been
         delivered pursuant to Section 6.01(g)(vii), as shown in such Compliance
         Certificate, to (y) the sum of EBITDA of the Borrower and its
         Subsidiaries for the period of four Fiscal Quarters ending on such last
         day, as shown in such Compliance Certificate, and (ii) the Leverage
         Ratio on such last day, as set forth in such Compliance Certificate.

                                       3

<PAGE>   4

Applicable Facility Fee Rate

<TABLE>
<CAPTION>

         Consolidated Total Debt                     If Leverage Ratio
               to EBITDA                             is less than or        If Leverage Ratio
          (rolling four quarter)                     equal to 0.35          is greater than 0.35
          ----------------------                     ------------------     --------------------
<S>                                                  <C>                     <C>
         If Less than .50                                +0.200%                 +0.250%

         If Less than 1.00 but greater than              +0.275%                 +0.325%
            or equal to .50

         If Less than 1.50 but greater than              +0.325%                 +0.350%
            or equal to 1.00

         If Greater than or equal to 1.50                +0.350%                 +0.375%
</TABLE>


                  (iii) on any day when Borrower is not in Collateral Status,
         but an Excess Purchase Price Amount exists, the Applicable Facility Fee
         Rate will be a percentage, calculated according to the following
         formula:

       Applicable Facility Fee Rate  =    EPPA * 0.150%  +    (APP - EPPA) * AF
                                          -------------       -----------------
                                                APP                   APP

         WHERE:

                  EPPA    =         the Excess Purchase Price Amount on such
                                    day, provided, that, in the event the
                                    Borrower has not deposited, and for so long
                                    (but only for so long) as Borrower has not
                                    deposited an amount equal to such Excess
                                    Purchase Price Amount into the Collateral
                                    Account on such day in accordance with
                                    Section 6.01(h), "EPPA" on such day shall be
                                    an amount equal to the amount on deposit in
                                    the Collateral Account on such day;

                  APP     =         the aggregate of the Purchase Prices of
                                    all Notes which are outstanding or, if such
                                    day is a Purchase Date, to be issued on such
                                    Purchase Date (after giving effect to any
                                    Notes which will be repaid on such Purchase
                                    Date); and

                  AF      =         the Applicable Facility Fee Rate that
                                    would have been in effect on such day
                                    pursuant to Section 3.01(b)(ii) if the
                                    Excess Purchase Price Amount on such day had
                                    not been greater than zero.

                  (iv) Except to the extent provided in the definition of "EPPA"
         above, the determination of the Applicable Facility Fee Rate for
         purposes of this Section 3.01(b) shall be made on each Purchase Date
         and such determination shall apply to each day during the period from
         such Purchase Date to, but excluding, the next succeeding Purchase
         Date.".

         Section 1.4 Amendment to Section 4.02(c). Section 4.02(c) of the
Agreement is hereby amended and restated to read in its entirety as follows:

                                       4

<PAGE>   5



         "(c) On such Purchase Date (i)(x) the Borrower is not in Collateral
         Status, and (y) no Excess Purchase Price Amount will exist, or (ii) the
         aggregate amount of cash and Qualifying Investment (or in the case of
         Qualifying Investments, principal equivalent amount) contained in the
         Collateral Account (including any proceeds of payment of the Purchase
         Prices of Notes on such Purchase Date which are to be disbursed into
         the Collateral Account pursuant to Section 1.04) shall be not less than
         (A) in the event Borrower is in Collateral Status on such Purchase
         Date, the aggregate of the Purchase Prices of all Notes purchased on
         any Purchase Date on which Borrower was in Collateral Status and which
         are outstanding or to be issued on such Purchase Date (after giving
         effect to any Notes which will be repaid on such Purchase Date), or (B)
         in the event an Excess Purchase Price Amount will exist on such
         Purchase Date, such Excess Purchase Price Amount.".

         Section 1.5 Amendment to Section 6.01(h). Section 6.01(h) of the
Agreement is hereby amended and restated to read in its entirety as follows:

         "(h)     Maintenance of Collateral Account.

                  (i)    Borrower agrees to:

                           (A) as specified in the Collateral Account
                  Agreement, maintain the Collateral Account at BofA;

                           (B) execute and deliver to BofA the Collateral
                  Account Agreement in form and substance satisfactory to BofA
                  covering all cash, Cash Equivalent Investments and other
                  investments which are from time to time maintained in the
                  Collateral Account (which investments shall be in form and
                  substance approved by BofA at the time such Collateral Account
                  Agreement is delivered, shall be of the Required Credit
                  Quality, and shall, if required by BofA, be made in the name
                  of BofA);

                           (C) (i) on each Purchase Date, deposit or maintain
                  cash and other such Qualifying Investments in such Collateral
                  Account at BofA in an aggregate amount (or, in the case of
                  Qualifying Investments, principal equivalent amounts) which is
                  not less than (x) if the Borrower is in Collateral Status on
                  such Purchase Date, the aggregate of the Purchase Prices of
                  all Notes purchased on any Purchase Date on which Borrower was
                  in Collateral Status and which are outstanding or to be issued
                  on such Purchase Date (after giving effect to any Notes which
                  will be repaid on such day), and (y) if an Excess Purchase
                  Price Amount will exist on such Purchase Date, such Excess
                  Purchase Price Amount, and (ii) not withdraw

                                       5

<PAGE>   6

                  any amounts or investments from such Collateral Account
                  except as permitted by the Collateral Account Agreement;

                           (D) deliver to BofA such consents as may be required
                  under the Bank Credit Agreement and Bank Revolver (and all
                  other agreements or instruments affecting Borrower) to the
                  delivery of such Collateral Account Agreement and collateral;
                  and

                           (E) deliver to BofA such resolutions, incumbency
                  certificates, opinions of counsel and other documents as BofA
                  may require with respect to authorization, enforceability,
                  legality, perfection, lack of conflict and other matters
                  required by BofA with respect to such Collateral Account
                  Agreement and the collateral covered thereby.

                  (ii)     As used in herein:

                           (A) "Collateral Status" means any Purchase Date on
                  which any of the following conditions have not been satisfied:

                                    (I) as of the last day of the immediately
                           preceding Fiscal Quarter for which a Compliance
                           Certificate has been delivered pursuant to Section
                           6.01(g)(vii) (a) if such Fiscal Quarter is the fourth
                           Fiscal Quarter of 1999 or the first Fiscal Quarter of
                           2000, the Consolidated Net Loss of the Borrower and
                           its Subsidiaries, as shown in such Compliance
                           Certificate, is less than $42,500,000 for such fourth
                           Fiscal Quarter or $35,000,000 for such first Fiscal
                           Quarter, and (b) if such Fiscal Quarter is any other
                           subsequent Fiscal Quarter, the Consolidated Net
                           Income and Consolidated Operating Income of the
                           Borrower and its Subsidiaries, as shown in such
                           Compliance Certificate, is at least zero;

                                    (II) (a) as of the last day of the
                           immediately preceding Fiscal Quarter, for which a
                           Compliance Certificate has been delivered pursuant to
                           Section 6.01(g)(vii), the Available Cash Amount, as
                           shown in such Compliance Certificate, is greater than
                           $125,000,000, or (b) as of the last day of the
                           immediately preceding Fiscal Quarter, for which a
                           Compliance Certificate has been delivered pursuant to
                           Section 6.01(g)(vii), the Available Revolver Amount,
                           as shown in such Compliance Certificate, is greater
                           than $50,000,000, or

                                    (III) Borrower shall have delivered, prior
                           to 10:00 a.m. (San Francisco time) on the LIBOR
                           Fixing Date for such Purchase Date, a Notice

                                       6

<PAGE>   7

                           of Borrowing pursuant to Section 1.03(b) indicating
                           that Borrower will not be in Collateral Status as of
                           such Purchase Date;

                           (B) "Available Cash Amount" means, with respect to
                  the last day of any Fiscal Quarter, the U.S. Dollar equivalent
                  (determined in accordance with GAAP) of all unrestricted cash
                  and unrestricted Cash Equivalent Investments owned by the
                  Borrower and its Subsidiaries, all as set forth in the
                  Compliance Certificate as of such last day which was delivered
                  pursuant to Section 6.01(g)(vii). It is understood and agreed
                  that, with respect to this Section 6.01(h)(ii)(B), the
                  "Available Cash Amount" shall include, without duplication (i)
                  any unrestricted cash which is received by the Borrower in
                  respect of the Purchase Price for any outstanding Note
                  (provided, however, that under no circumstances shall the
                  "Available Cash Amount" include any cash or Cash Equivalent
                  Investments deposited into the Cash Collateral Account), and
                  (ii) any cash or Cash Equivalent Investments for which the
                  only restriction on such cash or Cash Equivalent Investments
                  is that they are subject to a lien of the Collateral Agent and
                  the other Secured Parties as proceeds of the Collateral (as
                  used in clause (II) of this Section 6.01(h)(ii)(B),
                  "Collateral Agent," "Secured Parties" and "Collateral" each
                  have the meanings assigned to such terms in the Bank Credit
                  Agreement).

                            (C) "Available Revolver Amount" means, with respect
                  to the last day of any Fiscal Quarter, the sum, as set forth
                  in the most recent Compliance Certificate as of such last day
                  which was delivered pursuant to Section 6.01(g)(vii), of (I)
                  the excess of (x) the aggregate of the lender commitments
                  under the Bank Credit Agreement as of the last day of such
                  Fiscal Quarter, over (y) the sum of (1) the outstanding
                  principal amount of all loans, advances and outstanding letter
                  of credit reimbursement obligations under the Bank Credit
                  Agreement as of the last day of such Fiscal Quarter, plus (2)
                  the aggregate outstanding face amount of all letters of credit
                  under the Bank Credit Agreement as of the last day of such
                  Fiscal Quarter, and (II) the excess of (x) the aggregate of
                  the lender commitments under the Bank Revolver as of the last
                  day of such Fiscal Quarter, over (y) the outstanding principal
                  amount of all loans, advances and other extensions of credit
                  to the Borrower under the Bank Revolver as of the last day of
                  such Fiscal Quarter.

                  (iv) The determination of whether or not Borrower is in
         Collateral Status for purposes of this Section 6.01(h) shall be made on
         each Purchase Date and such determination shall apply from such
         Purchase Date to the next succeeding Purchase Date.

                  (v) For purposes of determining whether or not Borrower is in
         compliance with clauses (I), (II) and (III) of the definition of
         Collateral Status, the Consolidated Net Income, Consolidated Net Loss,
         Consolidated Operating Income, Consolidated Operating Loss, Available
         Cash Amount and Available Revolver Amount shall be calculated as set
         forth in

                                       7

<PAGE>   8

         this Section 6.01(h) and such calculation shall be used in determining
         whether or not Borrower is in Collateral Status from the first
         Purchase Date after the delivery of such Compliance Certificate to,
         but excluding, the first Purchase Date after which Borrower has
         delivered a new Compliance Certificate for the next Fiscal Quarter of
         the Borrower as provided herein."

                  Section 1.6 Amendment to Section 6.02(a). Section 6.02(a) of
         the Agreement is hereby amended and restated to read in its entirety as
         follows:

                  "(a) Profitability. Not permit (a) with respect to the fourth
         Fiscal Quarter of 1999 and the first Fiscal Quarter of 2000, the
         Consolidated Net Loss of the Borrower and its Subsidiaries to be
         greater than $42,500,000 for such fourth Fiscal Quarter or $35,000,000
         for such first Fiscal Quarter, and (b) with respect to any other
         subsequent Fiscal Quarter of the Borrower and its Subsidiaries, the
         Consolidated Net Income or Consolidated Operating Income of the
         Borrower and its Subsidiaries to be less than zero.".

         Section 1.7 Amendment to Definition of Facility Limit. The definition
of Facility Limit in Schedule I to the Agreement is hereby amended and restated
in its entirety as follows:

         "`Facility Limit' means $120,000,000, as such amount may be reduced
pursuant to Section 1.07.".

         Section 1.8 Amendment to Schedule I. Schedule I to the Agreement is
hereby amended by inserting the following definitions in their alphabetically
determined places, and to the extent any such definition is already defined in
Schedule I, such definitions are amended and restated in their entirety:

         "Available Cash Amount" is defined in Section 6.01(h)(ii)(B).

         "Available Revolver Amount" is defined in Section 6.01(h)(ii)(C).

         "Collateral Status" is defined in Section 6.01(h)(ii)(A).

         "EBITDA" means, with respect to any period, for the Borrower and its
Subsidiaries on a consolidated basis, determined in accordance with GAAP, the
sum of (a) Net Income (or Net Loss) for such period determined without giving
effect to the proviso to the definition of Net Income or Net Loss, as the case
may be, plus (b) all amounts treated as expenses for depreciation, interest and
the amortization of intangibles of any kind to the extent included in the
determination of such Net Income (or Net Loss), plus (c) all accrued taxes on or
measured by income to the extent included in the determination of such Net
Income (or Net Loss), plus (d) all restructuring and litigation charges recorded
during any Fiscal Quarter of 1999 and the first and

                                       8

<PAGE>   9

second Fiscal Quarters of 2000 to the extent included in the determination of
such Net Income (or Net Loss).

         "Excess Purchase Price Amount" means, with respect to any Purchase
Date, an amount equal to the excess, if any, of (x) the aggregate of the
Purchase Prices of all Notes which are outstanding or to be issued on such
Purchase Date (after giving effect to any Notes which will be repaid on such
Purchase Date), over (y) $50,000,000.

         "Leverage Ratio" means, with respect to any Person, the ratio that (i)
Consolidated Total Debt of such Person bears to (ii) the Consolidated Total
Capital of such Person.

         "Net Income" means, with respect to any Person for any period, net
income of such Person, as determined by such Person in accordance with GAAP,
provided, that, with respect to the fourth Fiscal Quarter of 1999, the first
Fiscal Quarter of 2000, and the second Fiscal Quarter of 2000, cumulative
pre-tax non-cash restructuring charges, and write-offs and write-downs of assets
classified as non-cash assets, in each case, recognized in accordance with GAAP
during such Fiscal Quarter and in an amount not to exceed $50,000,000 in the
aggregate during such Fiscal Quarters, shall be excluded from the calculation of
the Consolidated Net Income of Borrower and its Subsidiaries for such Fiscal
Quarter.

         "Net Loss" means, with respect to any Person for any period, net loss
of such Person, as determined by such Person in accordance with GAAP, provided,
that, with respect to the fourth Fiscal Quarter of 1999, the first Fiscal
Quarter of 2000, and the second Fiscal Quarter of 2000, cumulative pre-tax
non-cash restructuring charges, and write-offs and write-downs of assets
classified as non-cash assets, in each case, recognized in accordance with GAAP
during such Fiscal Quarter and in an amount not to exceed $50,000,000 in the
aggregate during such Fiscal Quarters, shall be excluded from the calculation of
the Consolidated Net Loss of Borrower and its Subsidiaries for such Fiscal
Quarter.

         "Operating Income" means, with respect to any Person for any period,
operating income of such Person, as determined by such Person in accordance with
GAAP, provided, that, with respect to the fourth Fiscal Quarter of 1999, the
first Fiscal Quarter of 2000, and the second Fiscal Quarter of 2000, cumulative
pre-tax non-cash restructuring charges, and write-offs and write-downs of assets
classified as non-cash assets, in each case, recognized in accordance with GAAP
during such Fiscal Quarter and in an amount not to exceed $50,000,000 in the
aggregate during such Fiscal Quarters, shall be excluded from the calculation of
the Consolidated Operating Income of Borrower and its Subsidiaries for such
Fiscal Quarter.

         "Operating Loss" means, with respect to any Person for any period,
operating loss of such Person, as determined by such Person in accordance with
GAAP, provided, that, with respect to the fourth Fiscal Quarter of 1999, the
first Fiscal Quarter of 2000, and the second Fiscal Quarter of 2000, cumulative
pre-tax non-cash restructuring charges, and write-offs and write-downs of assets
classified as non-cash assets, in each case, recognized in accordance with GAAP
during

                                       9


<PAGE>   10

such Fiscal Quarter and in an amount not to exceed $50,000,000 in the aggregate
during such Fiscal Quarters, shall be excluded from the calculation of the
Consolidated Operating Loss of Borrower and its Subsidiaries for such Fiscal
Quarter.

         Section 1.9 Amendment to Exhibit 1.03(b). Exhibit 1.03(b) to the
Agreement is hereby amended and restated to read in its entirety as set forth in
Schedule A attached hereto.

         Section 1.10 Amendment to Exhibit 6.01(g)(vii). Annex I to Exhibit
6.01(g)(vii) to the Agreement is hereby amended and restated to read in its
entirety as set forth in Schedule B attached hereto.

                                   ARTICLE II
                         REPRESENTATIONS AND WARRANTIES

         Section 2.1 Representations and Warranties. Borrower hereby represents
and warrants to BofA that:

                  (a)  Representations and Warranties. The representations and
         warranties of Borrower contained in the Agreement are true and correct
         on and as of the date of this Amendment as though made on and as of
         such date, and

                  (b)  No Termination Event. Both before and after giving effect
         to this Amendment, no event shall exist that constitutes a Termination
         Event or an Unmatured Termination Event.

                                   ARTICLE III
                                  MISCELLANEOUS

         Section 3.1 Agreement Document Pursuant to Agreement. This Amendment is
an Agreement Document executed pursuant to the Agreement and shall be construed,
administered and applied in accordance with all of the terms and provisions of
the Agreement.

         Section 3.2 Successors, Transferees and Assigns. This Amendment shall
be binding upon and inure to the benefit of the parties hereto and their
respective successors, transferees and assigns.

         Section 3.3 Execution in Counterparts. This Amendment may be executed
by the parties hereto in several counterparts, each of which shall be deemed to
be an original and all of which shall be taken together as one agreement.


                                       10

<PAGE>   11
         Section 3.4 Governing Law. THIS AMENDMENT SHALL BE A CONTRACT MADE
UNDER, GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE INTERNAL LAWS OF THE
STATE OF CALIFORNIA WITHOUT REGARD TO ITS PRINCIPLES OF CONFLICTS OF LAWS.

         Section 3.5 Reaffirmation of Agreement. As amended and supplemented by
this Amendment, the Agreement remains in full force and effect and is hereby
reaffirmed, ratified and confirmed in all respects. From and after the date
hereof, all references to the Agreement in any agreement, instrument or document
shall be references to the Agreement as amended and supplemented hereby.

         Section 3.6 Headings. The various captions in this Amendment are
provided solely for convenience of reference and shall not affect the meaning or
interpretation of any provision of this Amendment.

         Section 3.7 Complete Agreement. The Agreement (including this Amendment
and the Exhibits and Schedules to the Agreement and this Amendment) and the
other Agreement Documents contain the entire understanding of the parties with
respect to the transactions contemplated hereby and thereby and supersedes all
prior arrangements or understandings with respect thereto.

         Section 3.8 Severability. Whenever possible, each provision of this
Amendment will be interpreted in such a manner as to be effective and valid
under applicable law, but if any provision of this Amendment is held to be
prohibited by or invalid under applicable law, such provision will be
ineffective only to the extent of such prohibition or invalidity, without
invalidating the remainder of this Amendment, except to the extent that such
prohibition or invalidity would constitute a material change in the terms of
this Amendment taken as a whole.


                                       11



<PAGE>   12


         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed by their respective officers thereunto duly authorized as of the day
and year first above written.


                                              STORAGE TECHNOLOGY CORPORATION


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

                                              BANK OF AMERICA, N.A.
                                              (formerly Bank of America National
                                               Trust and Savings Association)


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



                                      S-1