ItzGoinDwn:
I'm thinking that either your Cingular 8125 or your router is running with IEEE 802.1X authentication enabled. I'd recommend disabling it in your router or Pocket PC if it is enable unless you actually have an authentication server setup (I doubt it).
Here's a quick check. If you can connect fine with your laptop and you know that IEEE 802.1X is not enabled, then you know that it is definetely your Cingular 8125. You can change those settings in the connection settings.
You can learn more about 802.1X Authenication here:
IEEE 802.1X Authentication for Wireless Connections: The Cable Guy, April 2002
Let me know if my assumption is correct. If not we can continue looking elsewhere.
-Tim