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 ...
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.