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Exhibit 22
The subsidiaries of American TeleSource International, Inc. are as follows:
State or Other Company Jurisdiction of Incorporation
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ATSI Comunicaciones, S.A. de C.V. ("ATSI-COM") Mexico
American TeleSource International, Inc. Canada
American TeleSource International, Inc. Texas
American TeleSource International de Mexico, S.A. de C.V. Mexico
GlobalSCAPE, Inc. Delaware
Sistema de Telefonia Computarizada, S.A. de C.V. ("Computel") Mexico
Servicios de Infraestructura, S.A. de C.V. ("Sinfra") Mexico
TeleSpan, Inc. ("TeleSpan") Texas
ATSI de CentroAmerica, S.A. Costa Rica
