Did you run the voip setup program? Are you sure you have the info entered properly.
You might want to try installing sjphone (
http://www.freewarepocketpc.net/ppc-...1-60-303c.html) and see if you can get it to work. If you can, then you know for sure you've got the settings right.
In my cause I used a gizmo5 account, and it took me some tinkering with sjphone to finally get it to where I knew the settings were good, THEN I went and did the voipsetup program and it worked just fine.
The only issue I have is that the todayscreen plugin doesn't work - however I've heard that this is the case for most people.