Ooops, yes, most times. I should have pointed that out since I live in a USCC home area and my phone always shows "Extended Network" and dialing *228(anything) gets me nowhere as well.
Sorry about that. Also, what is your basband version? If you do update your baseband, know that you had better not be roaming when you do that as well, since you will have to dial *228 after that as well.