I did what man ko kura said, and still att detected my iphone. I was reading somewhere, whenever u connect ur iphone to itunes it sends ur imei number to att and thats how they find it out, not sure if this is true. There was a hack called ziphone for iphone but its available for iphone 2g and below that fakes ur imei and att will think its some non smart phone. Good luck, let me know if got it working.