I’m not so sure about the GPRS thing in Cali tho. Even in HK, every phone has something different to setup (like kai920 says). From what i remember, you just need to get the proxy servers etc right so that the phone finds the right server to access the net. Could you look at the configurations/setups of your other friends in Cali who access gprs on cingular and then try and copy their configurations?
Another thought i had was that cingular might have personal accounts for gprs usage and they’ve barred your account to force you to use their phones for these cool functions… maybe….
sorry can’t be more solid jason.