I had a similar problem whilst writing a RAS dialer for the Casio IT600 running WinCE.
The dialer could make a connection, but when I tried to actually navigate to a page using IE on the handheld. The request was unsuccesful.
Basically, the issue was that the routing table on the handheld took the priority of using the ActiveSync connection rather than the GPRS one. The ActiveSync connection was consequently (but fortunately) being blocked by our firewall. If the connection had got through it would be impossible to test my dialer.
The first solution I found was to implement a descent amount of process logging code which wrote to a file. This would allow the handheld to be removed from the dock yet still log information. I then took the handheld from the cradle and hit the 'dial' button.
After this I was able to connect to the interweb through the GPRS radio.
However, this is not the best option for actually allowing us to debug the connection.
Your problem seems to be the opposite. You CAN connect to the interweb but it channels through your PC connection. The best way to alleviate this, is to write an entry to the handhelds routing table explicitly stating not to use the PC connection (i.e. block the handheld access to your gateway). That should work.
Robsta
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