Host Routing Table

I have an Unlocked T-Mobile Blackberry 8320 handset. It is working fine. I can make and receive calls/SMS. I can browse internet through Wi-Fi and GPRS browser. However Blackberry services are not working on the handset. I got Blackberry plan already activated. When I call my service provider for the handset settings, they ask me to go to the host routing table, and register the handset. I have tried it in manual selection mode, and taken out the battery and SIM card also after the registration message sent option. Still the gprs is coming in small letters, and my handset is not registering. Now the service providers are saying that my handset is faulty. I cant believe it. Please let me know the solution.

By manual network selection, I mean setting the Mobile Network Selection mode to manual instead of automatic. I was told to do so, before going to the Host Routing Table. Still, it did not work.

Is it possible that in the unlock process, the Blackberry services still remain locked, while other services remain unlocked. Is there any provision of selective unlocking? In my mind, if a mobile is unlocked its all the services should be unlocked.

Kindly help.
Thanks