EXHIBIT 23

                    CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS

     As independent public  accountants,  we hereby consent to the incorporation
of our  report  dated  March 21,  2000,  included  in this Form  10-K,  into the
Company's  previously filed Amendment No. 3 to Form S-4  Registration  Statement
No.  333-25355  and  post-effective  Amendment  No.  4 on Form  S-2 to Form  S-1
Registration Statement No. 33-59279.



                                             ARTHUR ANDERSEN LLP


Vienna, VA
March 29, 2000