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                                                                     Exhibit 4.5

                                SAP AMERICA, INC.
                       401(k) PROFIT SHARING PLAN & TRUST
                                 AMENDMENT 99-1

      Pursuant to the power reserved to SAP America, Inc. under Section 14.1 of
the SAP America, Inc. Profit Sharing Plan & Trust (the "Plan") as set forth in
the Vanguard Prototype 401(k) Savings Plan (the "Master Document") and its
corresponding Adoption Agreement (the "Adoption Agreement"), the Plan is hereby
amended, effective January 1, 1997 (except as expressly indicated otherwise), as
follows:

      1. Section 2.6 of the Master Document is hereby amended by changing the
reference to "Section 2 of the Adoption Agreement" in the first sentence thereof
to refer to "Section 3 of the Adoption Agreement."

      2. Article 2.6(a) of the Master Document is hereby amended, effective
January 1, 1999 to read, in its entirety, as follows:

      "(a) the Compensation of each Participant for a Plan Year shall include
      all Employee Pre-Tax Contributions made to the plan on behalf of the
      participant for the Plan year and all pre-tax elective contributions made
      to any other plan by the employer for the Plan Year pursuant to a salary
      reduction agreement with the Participant which are not includable in the
      Participant's gross income under Section 125, 402(e)(3), 402(h) or 403(b)
      of the Code, provided that the Employer has elected to treat all such
      pre-tax elective contributions as compensation with respect to all
      employees under all plans of the Employer; and"

      3. Section 3 of the Adoption Agreement is amended, effective January 1,
1999, by deleting all current selections thereunder and by instead selecting the
box captioned "wages for withholding purposes excluding certain items," by
checking the box captioned "other (specify)" under such item, and by inserting
the following items in the line following such box as items excluded from
compensation:

      "(i) amounts contributed by the Employer to the Plan, (ii) fringe
      benefits, (iii) workers' compensation and unemployment benefits, (iv)
      tuition advancements and reimbursements, (v) relocation and housing
      advancements and reimbursements, (vi) cost of living adjustments (vii)
      amounts designated by the Employer as severance payments in connection
      with an Employee's separation from employment, (viii) distributions from
      Employer sponsored nonqualified deferred compensation plans and earnings
      thereon, (ix) sign-on bonus payments provided to an Employee in connection
      with commencement of employment, and (x) for purposes of determining
      Employer Profit Sharing Contributions pursuant to Article 4.11 and
      Employer Matching Contributions pursuant to Article 4.6, amounts in excess
      of $100,000."


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      4. Article 4.11 of the Master Document is amended in its entirety to
provide as follows:

      "4.11 Employer Profit Sharing Contributions

            (a) The Committee shall, at its discretion, credit to each eligible
            Participant's Employer Profit Sharing Contribution Account, a
            contribution in an amount which is in the same proportion that each
            Participant's Compensation for the Plan Year bears to the total
            Compensation of all such Participants for the Plan Year. In order to
            qualify for a Profit Sharing Contribution a Participant must be
            credited with a Year of Service and be actively employed by the
            Employer on the last day of the Plan Year to which the Profit
            Sharing Contribution is attributable. Notwithstanding the preceding
            sentence, a Participant shall be entitled to a Profit Sharing
            Contribution if such Participant (i) completes six (6) consecutive
            months of employment with the Employer during the Plan Year in which
            employment commences and is actively employed by the Employer on the
            last day of the Plan Year to which the Profit Sharing Contribution
            is attributable, or (ii) commenced employment with the Employer on
            or before July 1 of the Plan Year to which such Profit Sharing
            Contribution is attributable and thereafter during such Plan Year
            dies, incurs a Disability or retires on or after the Participant's
            attainment of Normal Retirement Age."

      5. The "Discretionary Formula" paragraph within Section 7 of the Adoption
Agreement is hereby amended by striking the second sentence currently appearing
therein and replacing it with the following sentences:

      "Employer Nonelective Contributions shall be allocated to the Employer
      Nonelective Contribution Accounts of Participants who Participated in the
      Plan at any time during the Plan Year, with the exception of Employer
      Profit Sharing Contributions, which shall be allocated to the Employer
      Profit Sharing Contribution Accounts of Participants who meet the
      eligibility requirements set forth in Article 4.11 of the Plan as amended.
      Employer Nonelective Contributions, including Employer Profit Sharing
      Contributions shall be allocated in accordance with the formula set forth
      in Article 4.11 of the Plan as amended."

      6. Article 6.4 of the Master Document is hereby amended in its entirety to
provide as follows:

      "Forfeitures arising from Employer Profit Sharing Contributions and/or
      Employer Matching Contributions shall be reallocated in the same manner as
      Employer Profit Sharing


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      Contributions are allocated pursuant to Article 4.11 as amended, with the
      exception that the determination and allocation of forfeitures arising
      from Employer Matching Contributions shall be limited to Participants
      eligible for Employer Matching Contributions for the Plan Year. In order
      to qualify for an allocation of forfeitures in a Plan Year, a Participant
      must be credited with a Year of Service and be actively employed by the
      Employer on the last day of the Plan Year to which the forfeiture is
      attributable. Notwithstanding the preceding sentence, a Participant shall
      be entitled to a forfeiture allocation if such Participant (i) completes
      six (6) consecutive months of employment with the Employer during the Plan
      Year in which employment commences and is actively employed by the
      Employer on the last day of the Plan Year to which the forfeiture
      allocation is attributable, or (ii) commenced employment with the Employer
      on or before July 1 of the Plan Year to which such forfeiture allocation
      is attributable and thereafter during such Plan Year dies, incurs a
      Disability or retires on or after the Participant's attainment of Normal
      Retirement Age."

      WHEREFORE, I have executed the foregoing amendment this _________ day of
______________________________ , 199 ______.


                                           By:
                                              ----------------------------------

                                           Name: Lawrence Kleinman
                                                --------------------------------

                                           Title: Vice President Human Resources
                                                 -------------------------------


Witness: _____________________


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