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                                                                    EXHIBIT 23.1

                                                                          [LOGO]

                   CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS

    As independent public accountants, we hereby consent to the inclusion in
this Form 8-K of our report dated August 31, 2001. It should be noted that we
have not audited any financial statements of the company subsequent to
December 29, 2000 or performed any audit procedures subsequent to the date of
our report.

                                          /s/ Arthur Andersen LLP

Vienna, VA
October 1, 2001