Some owners of Apple's new iPhone 4S have been hit with SIM card error messages, even if they are connected to a CDMA carrier that does not use SIM cards. One reader ...

IPhone 4 compatible with the CDMA 2000 system was announced for the US biggest mobile phone company "Verizon" this January, but notice whether KDDI which supports the same communication method will ...

Does Sprint even offer GSM service? If not, I don't see how your Razr would work. The Sanyo is a CDMA phone. IIRC, only Cingular and T-Mobile offer GSM service in the US.