G1 Matches SIM card Data of MCC / MNC with these Setting and then try to use that. Settings. is this why we cant use the the $5.99 package from T-Mobile? like i said in another post my sim works in all other phones but not this one i think the settings that are their now Mcc:310 and the MNC:260 are for 3G Network
I think MCC and MNC depend on the place (and carrier) you are. In Germany (T-Mobile) it's MCC 262 and MNC 01. Where are you located? You should ask someone from your location.