I bought a Motorola MXp200. I had to unblock it (from AT&T) then I had to do a SIM unlock. Got the program (unblock) and unlock codes from eBay. Total cost about $35. Both worked perfectly and now I can use with any SIM card in the world. Motorola and AT&T were not happy or friendly about it at all since Moto has a contract to block them to the AT&T network. I seriously doubt Cingular will totally unblock them. It will be easy for them to change over the SIM codes.