Not sure about this on N770 as I have a N800, but here goes. After the DUN profile is added to the 8525 delete the partnership on the IT and the phone, reboot the phone. Now re-pair. On the N800 we have an applet to manually set the phone (in the Control Panel). Designate the phone manually. Now create the Cingular connection profile (Packet Data, Phone Number: *99#, AP: wap.cingular, ID: WAP@CINGULARGPRS.COM, PW: CINGULAR1; case sensitive, the rest defaults).

Make sure BT is on and select the new Cingular connection. You should be good to go. The modem link software is not actually needed for BT connections, it is really the .dll's and DUN reg entries that we are using, and they are active as long as the phone is on and BT is active.

Ninja