[swammi]

I found this registry hack a while ago, and it always works for me...

HKEY_LOCAL_MACHINE\Comm\ConnMgr\Planner\Settings\
SuspendResume = GPRS_bye_if_device_off
CacheTime = xxx (where xxx are seconds before auto disconnect, for me the best value is 60)

You can have multiple lines in the 'SuspendResume' key, so I usually leave whatever is there alone, and just add this on another line. I never have a problem with calls, etc.

Hope this helps!