Según la wikipedia....
http://en.wikipedia.org/wiki/Android_(operating_system)
Cita:
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Video calling
Android does not support native video calling, but some handsets have a customized version of the operating system that supports it, either via the UMTS network (like the Samsung Galaxy S) or over IP. Video calling through Google Talk is available in Android 2.3.4 and later. Gingerbread allows Nexus S to place Internet calls with a SIP account. This allows for enhanced VoIP dialing to other SIP accounts and even phone numbers. Skype 2.1 offers video calling in Android 2.3, including front camera support.
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Parece que Android no las soporta de forma nativa aunque al parecer según que ROMs vienen modificadas para soportarlas. Independientemente del soporte a videollamadas sobre datos con aplicaciones de terceros.