[gazment]

A buddy of mine has a knock off iPhone from some eastern country and you wouldn't be able to tell the difference. He walked into the ATT store and activated it no problems and saved a few hundred dollars in purchasing the phone to boot. Don't go knocking the knock offs their are some pretty damn good ones out there.

However, i'm not sure if a knock off sprint would work unless you were to take a clean esn from a similar OEM device (thats junk) and program the phone with it before activation. Which is probably what is happening.