att go phone sim locked to phone, i want it in my iphone 3g?

[jackblackaries]

ive been going through some crazy moments with a friend who i just so happen to have my phone under.... well i decided to get away from him and that made me lose my number.... i bought a prepaid phone and activated it.... the sim card is locked to the prepaid phone (says att retards) but i want it to work in my iphone 3g....
when i take the sim out of the prepaid phone and put it in the iphone it says i have no signal, but i know it works just fine (hints the lock)...
how do i undo this so called lock?????? PLEASE HELP

[duckies]

the service you have may not be enough to use on a phone that requires internet in order to funtion... not all phones can use prepaid...

[evilattorney]

You don't. The sim won't work. ATT does not support the iPhone as a prepaid.