An article from InfoWorld notes that the FCC has approved (PDF) Friday a software defined radio made by Vanu..

The radio is for use as a cellular base station for GSM and will be capable of handling a variety of frequencies (important for GSM, since Europe uses 900MHz and 1.8GHz, the US and Canada use 850MHz and 1.9GHz, and other parts of the world may use yet different frequencies).

Press announcement by the company is here