EXHIBIT 99.257

12404 PARK CENTRAL DRIVE
DALLAS, TX 75251                                             [PEROTSYSTEMS LOGO]
972.340.6429
972.340.6081 FAX



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                           Post It Fax Note      7571          Date   5/22       #of pages   6
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                           To /s/ KEN SCOTT                    From   /s/ STEVE APPELT
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                           Co. Dept.                           Co.
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                           Phone #                             Phone # 614-324-4565
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                           Fax # 972-340-6081                  Fax #
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FAX

TO:       Steve Appelt             FROM:     Ken Scott
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FAX:      614.324.4591             PHONE:    972.340.6429
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PHONE:    614.324.4565             PAGES:    6
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RE:       NDA                      DATE:     May 21, 2001
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[ ] URGENT [ ] FOR REVIEW [ ] PLEASE COMMENT [ ] PLEASE REPLY [ ] PLEASE RECYCLE


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- - COMMENTS

Steve:

Attached is the signed NDA. Please initial the minor changes (I added our
company and address), sign and fax the executed agreement to me at 972.340.6081.


                           CONFIDENTIALITY AGREEMENT

This CONFIDENTIALITY AGREEMENT ("Agreement") is made and entered into by and
between AEP Energy Services, Inc. an Ohio corporation having a principal place
of business at 1 Riverside Plaza, Columbus, Ohio 43215 ("AEPES") and, Perot
Systems Corporation having a principal place of business at 12404 Park Central
Dr., Dallas, TX 75251 ("Company"). Company and AEP may be hereinafter referred
to individually as "Party" and collectively as the "Parties".


                                  WITNESSETH:

WHEREAS, AEPES and Company are considering a possible business relationship (the
"Transaction") by which the Parties would explore several business
opportunities, including a potential purchase of or participating ownership
interest in the

WHEREAS, each of the Parties and their affiliates are in possession of trade
secrets, technology, drawing specifications and/or other confidential
information relating to its businesses and business interests and may find it
desirable and necessary to exchange such information during the course of these
negotiations.

NOW, THEREFORE, In consideration of the mutual covenants contained herein, the
Parties agree as follows:

1.      CONFIDENTIAL INFORMATION. "Confidential Information" is defined to
        include any information (not included in Section 4 below) that is
        disclosed by or about either party and/or their affiliate(s) (the
        "Disclosing Party") to the other party and/or their affiliate(s) (the
        "Receiving Party") in connection with the Transaction, such as:

        a. Written information or machine readable data, including notes,
        reports, assessments, specifications, drawings, financial statements and
        projections, software and databases, customer information, sales and
        marketing strategies, and any other written information or machine
        readable data;

        b. Orally conveyed information, including but not limited to
        demonstrations;

        c. Any hardware, including but not limited to samples, devices and any
        other physical embodiments delivered to the Receiving Party; and



        d. Any documents jointly or separately generated by the Parties that
        reflect, interpret, incorporate, evaluate, or are derived from the
        information described above (such documents being hereinafter referred
        to as "Evaluation Material").

2.      CONFIDENTIALITY. For a period of two years from the date hereof, the
        Receiving Party agrees:

        a. to keep all Confidential Information confidential and not to copy,
        distribute, disclose or disseminate the Confidential Information in any
        manner to any person or entity, provided, however, that a limited number
        of copies of written materials may be made by the Receiving Party in
        order for the Receiving Party to adequately use the Confidential
        Information within the terms and conditions of this Agreement and that
        each copy is considered as Confidential Information and as an original
        in accordance with this Agreement; and

        b. not to disclose that the Evaluation Material has been generated, or
        that either Party and any entity identified in the Confidential
        Information may be considering a business relationship or have had, are
        having or propose to have any discussions with respect thereto.

        Notwithstanding the foregoing, the Receiving Party may disclose
        Confidential Information to those employees, officers, directors,
        agents, consultants, and advisors (collectively "Representatives") whose
        access is necessary to conduct the investigations and negotiations
        contemplated herein and who have been informed of the confidentiality
        restrictions contained in this Agreement. However, the Receiving Party
        may only disclose the Confidential Information to non-employee
        Representatives of the Company whose access is necessary if the
        non-employee Representatives are provided with a copy of this
        Confidentiality Agreement and agree to be bound by the terms of this
        Agreement.

        Each Party agrees to be responsible for the actions, uses and
        disclosures of any of its Representatives.

3.      OWNERSHIP AND USE OF CONFIDENTIAL INFORMATION. All Confidential
        Information except Evaluation Materials shall remain the property of the
        Disclosing Party. No license or other rights under any patents or other
        proprietary rights is granted or implied by the conveyance of the
        Confidential Information. The Receiving Party shall not use the
        Confidential Information for any purpose other than to effectuate the
        investigative and negotiation purposes of this Agreement.

4.      NON-CONFIDENTIAL INFORMATION. The restrictions and confidentiality
        obligations set forth in this Agreement shall not apply to Confidential
        Information which:

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        a.      is or becomes part of the public domain through no fault of the
                Receiving Party.
        b.      is disclosed to the Receiving Party by a
                third party when the Receiving Party reasonably believes the
                third party was not prohibited from making such disclosure;
        c.      was in the possession of the Receiving Party on a
                non-confidential basis prior to disclosure by the Disclosing
                Party;
        d.      subject to Section 8 hereof, is required to be
                disclosed to comply with any applicable law, order, regulation
                or ruling.

5.      PUBLIC DISCLOSURE. Neither Party shall make any press release or other
        public utterances of any kind regarding this Agreement, the Transaction,
        the information received pursuant to this Agreement or the contents of
        this Agreement without prior written consent of the other Party.

6.      DISPOSITION OF CONFIDENTIAL INFORMATION. Either Party (the "requesting
        Party") upon written request from the other Party, shall promptly, but
        in any case within 14 days, return to the other Party or destroy all
        Confidential Information, including without limitation, drawings and
        other documents, and any copies or summaries thereof, but excepting
        Evaluation Material. If the Confidential Information is destroyed, upon
        request, the other Party shall provide the requesting Party with a
        certificate stating that all Confidential Material has been destroyed.
        The Evaluation Material, including all copies thereof, will be destroyed
        by the other Party within said period and, if requested by the
        requesting Party, the other Party shall provide the requesting Party
        with a certificate of destruction.

7.      PROTECTION OF CONFIDENTIAL INFORMATION.  Each Party shall use efforts to
        protect the confidentiality of the Confidential Information which are
        at least as stringent as those which it uses to protect its own
        confidential information.

8.      LEGALLY REQUIRED DISCLOSURE.  If either Party becomes legally compelled
        to disclose any of the Confidential Information, or if such disclosure
        is necessary in order to obtain or maintain regulatory or governmental
        approvals, applications or exemptions, such Party will provide the other
        Party with as much advance notice as practicable to afford the
        opportunity to seek an appropriate protective order or other remedy to
        prevent or narrow the disclosure or to ensure that such information
        will continue to be treated in as confidential a manner as possible.
        In such cases, the Party may furnish only that portion of the
        Confidential Information which is legally required or necessary and
        shall cooperate with the other Party to enable it to obtain a protective
        order or other reliable assurance that confidential treatment will be
        accorded the same.

9.      TERM OF AGREEMENT.  This Agreement will be effective as of the date
        hereof and will terminate two years after its effective date.

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11.     WARRANTIES. Each Party acknowledges that other Party (including its
        trustees, directors, officers, employees, and agents) makes no express
        of implied representation or warranty as to the accuracy or completeness
        of any Confidential information and that the other Party shall have no
        liability arising out of or relating to the Party's or its
        Representatives' use of any Confidential Information.

12.     REMEDIES. Each Party understands and agrees that monetary damages would
        not be adequate remedy for a breach of this Agreement. In the event of
        any breach or threatened breach by either Party of this Agreement, the
        other Party shall be entitled to injunctive and other equitable relief,
        and that there shall be no pleading in defense thereto that there would
        be an adequate remedy at law. Such remedy shall be in addition to all
        other remedies available to it at law or in equity. The non-breaching
        Party shall also be entitled to recover its reasonable legal fees and
        expenses and costs in enforcing this Agreement or recovering damages for
        any breach hereof.

13.     NOTICES. Addresses for notices and requests are:

        AEP Energy Services, Inc.
        1 Riverside Plaza
        Columbus, Ohio 43215
        Attention: GENERAL COUNSEL

        PEROT SYSTEMS CORPORATION
        12404 PARK CENTRAL DR.
        DALLAS, TX 78251

        Attention: GENERAL COUNSEL

        Notices shall be in writing and shall be given to the designated
        representative, either by personal delivery or by the U.S. Mail,
        facsimile, or other similar means mutually agreeable to AEPES and the
        Company. All notices shall be effective upon receipt.

14.     APPLICABLE LAW. This Agreement shall be construed and enforced in
        accordance with the laws of the State of Ohio, without regard to the
        conflict of laws in effect therein.

15.     ASSIGNMENT. This Agreement may not be assigned, delegated or transferred
        by either Party in any way, without the prior written consent of the
        other Party, which consent shall not be unreasonably withheld or
        delayed. This Agreement shall be binding upon and shall inure to the
        benefit of the Parties hereto and their respective permitted successors
        and assigns.

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16.     ENTIRE AGREEMENT. This Agreement constitutes the entire Agreement
        between the Parties, supercedes any prior understandings or
        representations relating to the subject matter hereof, and shall not be
        subject to change or amendment except by subsequent written agreement
        signed by authorized representatives or the Parties. All provisions of
        this Agreement are severable, and the unenforceability of any of the
        provisions of this Agreement shall not affect the validity or
        enforceability of the remaining provisions of this Agreement.

17.     FINALIZATION OF TRANSACTION. Until AEPES and the Company have executed
        the documents necessary to finalize the Transaction, neither Party shall
        have any liability to the other Party with respect to a Transaction.

18.     NO WAIVER. No failure or delay by a Party in exercising any right, power
        or privilege hereunder shall operate as a waiver thereof, nor shall any
        single or partial exercise thereof preclude any other or further
        exercise of any other right, power or privilege hereunder.

19.     COUNTERPARTS; FACSIMILE EXECUTION. This Agreement may be executed in
        counterparts, with each executed counterpart having the same force and
        effect as the original counterpart. This Agreement shall be deemed
        binding upon the Parties if each Party executes this Agreement, sends
        the executed Agreement via facsimile to the other Party, and receives
        confirmation of receipt of the executed Agreement from the other Party.

IN WITNESS WHEREOF, the Parties hereto have executed this Agreement as of the
22ND day of May 2001.

AEP Energy Services, Inc.


By:     /s/                                 By:    /s/
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Title: SRVP - Administration                Title: Vice President
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       AEP Energy Services, Inc.                   Perot Systems Corp.


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