How can I disconnect GPRS within Windows Mobile 6 using VB.NET

I have an application written in vb.net (VS2005) running on a Windows Mobile
6 device. It uses the GPRS (GSM Data bearer) for its comms back to the
server. The comms are a standard connection within the device setup which
automatically connects when needed, as mobile 6 is designed to do .

My problem is sometimes the connection becomes problematic and the data I am
sending wont send. The only resolution is to manually disconnect the data
connection and then the system automatically starts it back up again and the
data starts flowing once again.

How can I disconnect the GPRS data bearer in code, does anyone know? Its
been suggested before that I use the ‘Comms Manager’, but that would appear
that I can only do that if I make the original connection via the comms
manager too. Where I just want to rely on the Windows Mobile comms to do that.