Here are the settings (Executive Summary: follow what is said on Ross Barkman's GPRS Info page (make sure telephone number is set to!!!) and use Ross's Nokia GPRS CID1 script:

In System Preferences->Network->Bluetooth:
-Set DNS Servers to
-Turn off IPv6
- Account Name: fido
- Password: fido
- Telephone (I kept getting this wrong!)
Bluetooth Modem:
-use Ross Barkman's Nokia GPRS CID1 script