People have been talking about the phone lock up. It's true! While I wouldn't call it a "lock up", it sure does slow your phone's response time down considerably. In fact, to an almost unusable state:
http://forum.ppcgeeks.com/showpost.p...2&postcount=57
WARNING: This may cause your phone to completely lock up. Making it so dead, you have to take the battery out and put it back in to use it.
Everyone do this: Go into the Phone app (Settings > Phone > Services), select Roaming and tap the Get Settings button. (Now the other poster has you changing the Roaming setting between Sprint, Automatic and Roaming and then it freezes after hitting OK -> OK) However, in my testing, I hit OK twice between EACH setting change, and then went back to the Roaming settings screen each time. After a few times the phone will lock up or slow to a crawl. It usually only takes 1-3 changes.