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                                                                    EXHIBIT 21.1
 
                         SUBSIDIARIES OF THE REGISTRANT
 
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NAME OF SUBSIDIARY                                                        JURISDICTION OF INCORPORATION
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CEO Telecommunications, Inc.                                              California
 
CEO California Telecommunications, Inc.                                   California
 
Helvey Com, Inc.                                                          California
 
T-One Corp.                                                               Delaware
 
Lucius Enterprises, Inc.                                                  California
 
STAR Telecommunications Australia PTY. Ltd.                               Australia
 
Romborg Holding, B.V.                                                     Netherlands
 
STAR Europe Ltd.                                                          United Kingdom
 
STAR Telecommunications Deutschland, GmbH                                 Germany
 
STAR Telecommunications Holding, GmbH                                     Germany
 
STAR Telecommunications France Holding                                    France
 
STAR Telecommunications France                                            France
 
STAR Telecommunications Switzerland, S.a.r.l.                             Switzerland
 
Grupo Industrial Arvilla S.A. de C.V.                                     Mexico
 
Servicios Sumosierra S.A. de C.V.                                         Mexico
 
Grupo Bunden, S.A. de C.V.                                                Mexico
 
Grupo Palafox-Toledo, S.A. de C.V.                                        Mexico
 
PT-1 Communications, Inc.                                                 New York
 
STAR Network, GmbH                                                        Germany
 
Morningside, S.A. de C.V.                                                 Mexico
 
Milhouse, S.A. de C.V.                                                    Mexico
 
United Digital Network of Texas, Inc.                                     Texas
 
Advanced Management Services, Inc.                                        Arizona
 
CTN--Custom Telecommunications Network of Arizona, Inc.                   Arizona
 
STAR Japan, Inc.                                                          Japan (51%)
 
Asian Datanet, Inc.                                                       Japan (50%)
 
United Digital Network, Inc.                                              Delaware
 
Phonetime Technologies, Inc.                                              Delaware
 
PT-1 Long Distance, Inc.                                                  Delaware
 
PT-1 Holdings I, Inc.                                                     Delaware
 
PT-1 Holdings II, Inc.                                                    Delaware
 
Nationwide Distributors, Inc.                                             Delaware
 
PT-1 Phonecard, L.P.                                                      Texas
 
Platform Services, L.P.                                                   Delaware
 
PT-1 Communications Puerto Rico, Inc.                                     Delaware
 
PT-1 Communications Canada, Inc.                                          Canada
 
Investment Services, Inc.                                                 Delaware
 
Bayonne, S.A. de C.V.                                                     Mexico
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