I finally got to talk to him in Bogota.

When he took the SIM card out of his mom's Blackberry into the AT&T 3GS, the iPhone works perfectly.

When he takes that same SIM card and places it in the original AT&T unlocked iPhone, he gets a message that the phone can only be used for emergency calls. Cannot even get to the keyboard. Not sure what else to try.

His brother is also bummed about the Sprint iPhone issue. He was sure the agent told him it would work.