Nope. They don't. I am an iPhone user but bought a Nexus one to develop on and put a sim card from an old dumb phone into it after disabling the data option on

Nope. They don't. I am an iPhone user but bought a Nexus one to develop on and put a sim card from an old dumb phone into it after disabling the data option on the phone. AT&T immediately recognized the smartphone and automatically added the data plan to my bill. When I called them they said I cannot even use my iPhone sim with the Nexus one as they come under two different data plans even though its costs the same freaking amount of money.