Sprint Touch autodisconnect data after idle

[acrh2]

Has anyone found a working registry hack to disconnect the data line after inactivity?

I think the constantly connected data line is responsible for at least 20% battery drainage in about 16 hours (or a work day).

I tried the regular
HKLM/Comm/Connmgr/Plannet/Settings/SuspendResume
= "#777 - Timeout after Cachetime","",""
but that didn't seem to work properly.
While the data line disconnection seemed to work ok, there was a severe lag in answering a call - if the data line was already connected, it would take 5-7seconds to get the call after pressing the green answer button.

When I deleted HKLM/Comm/Connmgr/Plannet/Settings/SuspendResume completely from the registry, the behavior was the same.
This makes me believe that "#777 - Timeout after Cachetime","","" is simply a bogus string.

Any ideas?