dial up connection on Windows Mobile 5.0 using RasDIal

We are developing a piece of code that can connect to internet using dial up.
We are using the microsoft API RasDial to do this. We have deployed the same
code on Pocket PC 2003 and it works without any issues.
But the same piece of code when built and deployed on a Windows Mobile 5.0
does not work. The API returns conenction success and the corresponding call
to getConnectStatus also returns that we are connected. But the internet
explorer is not able to connect to the internet, in other words, we are not
able to browse. We have tried all sort of things but in vain.
Could any one out there help us out in this context?