go here this is what I did to get my gps working with data blocked on verizon.
http://forum.ppcgeeks.com/showthread.php?t=53561&page=2 obviously if you have already upgraded the radio no need to do it again. but if you haven't I strongly suggest you do but find a program to backup all of your data because you will be flashing your phone. like I said this is the exact way I did my phone it may or may not work for you use at your own risk.