AMENDMENT NO. 1 TO ACCOUNT CONTROL AGREEMENT

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                                                                   EXHIBIT 10.31


                               AMENDMENT NO. 1 TO

      ACCOUNT CONTROL AGREEMENT BETWEEN CITIBANK, N.A. ("CITIBANK"), ALLIED
       WORLD ASSURANCE COMPANY LTD ("ALLIED WORLD") AND MELLON BANK, N.A.
          ("MELLON") DATED 19 SEPTEMBER 2002 (THE "CONTROL AGREEMENT")

Dated upon the date that the last signature is affixed and dated hereto.

In consideration of the agreements made in this Amendment Agreement and for good
and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, and intending to be bound, Citibank, Allied World and Mellon
(collectively, the "Parties") hereby agree as follows:

1.     The second and fourth bullet points and the wording following them in
      Section 3 shall be deleted and the remaining two bullet points shall be
      re-designated as Subsections 3.01 and 3.02 respectively.

2.     A new Subsection 3.03 shall be inserted as follows:

      "Pledgor shall not direct Bank to release any of the financial assets in
      the Account or to close the Account and Bank agrees that it will not
      release any of the financial assets in the Account or close the Account
      without Secured Party's consent. For this purpose the term "release" shall
      be broadly construed to include release for any purpose, including
      (without limitation) release for settlement of a sale, release for the
      purposes of substituting new financial assets, release "free" without
      consideration and any other manner of leaving the Account. Secured Party
      will consent to the release of the financial assets provided that with
      respect to such financial assets, the following procedure is adhered to:

      (a)    Pledgor will determine (the "Determination") that the financial
            assets remaining in the Account will be equal to or exceed the
            aggregate value determined by Secured Party from time to time (the
            "Required Account Value") and to determine this shall diligently and
            in good faith:

            (i)    determine that the financial asset is eligible as collateral
                  as specified in Exhibit A hereto; and

            (ii)   use the mark-to-market value provided by pricing services used
                  by Bank in connection with the valuation of financial assets
                  under similar account control arrangements or for Bank's trust
                  accounts, in each instance after applying the discount
                  specified in Exhibit A hereto; provided that in determining if
                  the remaining financial assets are sufficient Pledgor shall
                  use the mark-to-market values of the financial assets reported
                   by such services not more than the Business Day (as
                  hereinafter defined) prior to the withdrawal or distribution
                  of any financial asset. Any financial asset that cannot be
                  valued as provided herein and any financial asset subject to
                  Bank's lien specified in Section 4 shall have no value in
                  determining if the financial assets to remain in the Account
                  are sufficient for the purposes of meeting the Required
                  Account Value.

      (b)    If following the Determination, Pledgor has come to the reasonable
            conclusion that by requesting a financial asset to be released, the
            financial assets rema