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                                                                    Exhibit 10.3

Private & Confidential

                              DATED AUGUST 12, 2005

                            ELCOM INTERNATIONAL, INC.      (1)

                                   ELCOM, INC.             (2)

                                       AND

                           PA SHARED SERVICES LIMITED      (3)

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                            PARENT COMPANY GUARANTEE

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                                                          Confidential

THIS DEED is made on 12 August 2005

BY

      (1) ELCOM INTERNATIONAL, INC. whose registered office is at 10 Oceana Way,
      Norwood, MA 02062 AND

      (2) ELCOM, INC. whose registered office is at 10 Oceana Way, Norwood, MA
      02062 (together the "GUARANTORS");

IN FAVOUR OF

      (2) PA SHARED SERVICES LIMITED (registered number 05234104) whose
      registered office is at 123 Buckingham Palace Road, London SW1W 9SR; ("THE
      BENEFICIARY")

BACKGROUND

(A)   The Beneficiary and Elcom Systems Limited (registered number 2838561)
      whose registered office is Forest House,3-5 Horndean Road, Bracknell, RG12
      0XQ; ("ELCOM") (the "PRINCIPAL DEBTOR") are contemplating entering into a
      Sub-Framework Agreement (the "SUB-FRAMEWORK AGREEMENT") to assist in the
      provision of services to build and maintain the Zanzibar System under a
      framework agreement that the Beneficiary will sign with
      OGCbuying.solutions ("THE FRAMEWORK AGREEMENT").

(B)   ELCOM, the Beneficiary and PA Consulting Services Limited (registered
      number 00414220) whose registered office is at 123 Buckingham Palace Road,
      London SW1W 9SR; ("PACS") are also contemplating entering into a Revenue
      Share Agreement ("THE REVENUE SHARE AGREEMENT") at the same time, which
      will distribute subscription revenue that may be generated by the Zanzibar
      System.

(C)   PACS has agreed to provide a separate performance guarantee on behalf of
      PASSL in favour of OGCbuying.solutions for its obligations under the
      Framework Agreement and other associated agreements.

(D)   The Guarantors are the ultimate parent and direct parent company of the
      Principal Debtor and have agreed to guarantee the Principal Debtor's
      obligations under the Sub-Framework Agreement and the Revenue Share
      Agreement (together "THE AGREEMENTS") in accordance with the terms and
      conditions contained in this Deed.

IT IS AGREED that:

1     GUARANTEE

1.1   The Guarantors hereby guarantee to the Beneficiary that the Principal
      Debtor shall observe and perform all the obligations, commitments,
      undertakings, warranties and indemnities to be observed and/or performed
      on the part of the Principal Debtor under or pursuant to such Agreements.

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2     LIABILITY UNCONDITIONAL

      The Guarantors' liability under this Deed shall be joint and several and
      shall not be discharged, reduced or otherwise affected in any way by
      reason of (i) a Beneficiary giving the Principal Debtor time or any other
      concession, (ii) any composition, discharge, release or other variation of
      liability entered into with, or granted to, the Principal Debtor, (iii)
      the Beneficiary taking, holding, varying, realising or not enforcing any
      other security for the liabilities of the Principal Debtor under the
      Agreements, (iv) any amendment, variation or waiver of any provisions of
      any of the Agreements, (iv) any legal limitation or incapacity relating to
      the Principal Debtor or (vi) the invalidity or unenforceability of the
      obligations of the Principal Debtor under any of the Agreements. The
      Guarantors shall have no greater liability under this Deed than it would
      have had if the Guarantors had entered into the Agreements with the
      Beneficiary in place of the Principal Debtor.

3     CONTINUING GUARANTEE

      This Deed shall continue in effect notwithstanding any intermediate
      payment or partial settlement until all the obligations hereunder have
      been performed or fulfilled in full.

4     INDEMNITY

      The Guarantors shall indemnify and keep indemnified the Beneficiary on
      demand by the Beneficiary against all reasonable losses, actions, claims,
      costs, charges, expenses and liabilities incurred by the Beneficiary
      directly from the enforcement of any of the provisions of this Deed or
      occasioned by any breach by the Guarantors of any of its obligations to
      the Beneficiary under this Deed.

5     WAIVER OF GUARANTORS' RIGHTS

5.1   The Guarantors shall, not at any time during the validity of this Deed,
      exercise (otherwise than in accordance with the Beneficiary's lawful and
      timely instructions):

      (a)   its rights of subrogation, contribution and indemnity;

      (b)   its right to take the benefit of, share in or enforce any security
            or other guarantee or indemnity for the Principal Debtor's
            obligations held by the Beneficiary; and

      (c)   its right to prove or claim in the bankruptcy, liquidation,
            administration or other insolvency proceedings of the Principal
            Debtor.

      Any amount recovered as a result of the exercise of such rights shall be
      paid to the Beneficiary as soon as reasonably practicable following
      demand.

6     ASSIGNMENT

      The Beneficiary may assign or transfer any of its rights of obligations
      under this Deed to PACS in its absolute discretion. The Guarantors may not
      assign or transfer any of its rights or obligations under this Deed.

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                                                          Confidential

7     CUMULATIVE

      The Beneficiary's rights under this Deed are cumulative and not exclusive
      of any rights provided by law and may be exercised from time to time and
      as often as the Beneficiary deems expedient.

8     CHANGES IN OWNERSHIP OF PRINCIPAL DEBTOR

      If at any time during the course of the Agreements the identity of the
      shareholders in the Principal Debtor changes, the Guarantors shall give
      notice in writing to the Beneficiary setting out the identity of all
      shareholders in the Principal Debtor with their respective shareholdings
      and whether shares are held beneficially or otherwise.

9     NOTICES AND DEMANDS

      Any notice or demand for payment by the Beneficiary under this Deed shall
      be in writing and shall be deemed to have been served on the Guarantors if
      served in accordance with the notice provisions in the Agreements which
      shall be deemed to be incorporated in this Deed mutatis mutandis, or to
      such other address (and/or facsimile number) as the Guarantors may from
      time to time notify the Beneficiary in writing.

10    INVALIDITY

      If any provisions of this Deed become invalid, illegal or unenforceable in
      any respect under any law, the validity, legality and enforceability of
      the remaining provisions shall not in any way be affected or impaired.

11    THIRD PARTIES

      Any person, other than PACS, who is not a party to this Deed (including
      any employee, officer, agent, representative or sub-contractor of any
      party) shall not have the right to enforce any term of this Deed which
      expressly or by implication confers a benefit on that person without the
      express prior agreement in writing of the Guarantors and the Beneficiary,
      which agreement must refer to this clause 11.

12    LAW AND JURISDICTION

      This Deed is governed by English law and, for the benefit of the
      Beneficiary, the Guarantors hereby irrevocably and unconditionally submits
      to the exclusive jurisdiction of the courts of England.

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                                                          Confidential

IN WITNESS whereof this Deed has been executed and delivered as a deed by the
Guarantors on the date first specified above.

EXECUTED and DELIVERED)
as a DEED by          )
ELCOM INTERNATIONAL, INC.)

                                              /s/ Robert J. Crowell
                                              ------------------------
                                              DIRECTOR

                                              /s/ John E. Halnen
                                              ------------------------
                                              DIRECTOR/SECRETARY

EXECUTED and DELIVERED)
as a DEED by          )
ELCOM, INC.           )

                                              /s/ Robert J. Crowell
                                              ------------------------
                                              DIRECTOR

                                              /s/ John E. Halnen
                                              ------------------------
                                              DIRECTOR/SECRETARY

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