I am using an unlocked 650 with Vodafone GSM.
While using DUN with Bluetooth and a Mac everything works fine and I get a good connection. The only problem is that I get disconnected after a minute. Message says that "connection is disabled because other side does not respond. try again."

Connects with both Generic and Sony Ericsson modem scripts.

What is wrong?

Is it possible to connect through USB instead of using Bluetooth? How?