school wireless problem (2003 server

We are trying to setup a new wireless network within our school. We have installed a DLINK 2000AP+ onto our school network (Win 2003K) and configured it ok. However we cant get any of the laptops to connect to the server via the Access Point.

The laptops are set to obtain ip address automatically, but they get an invalid IP address and the wrong subnet mask (255.255.225.255) rather than 255.255.255.0

Even putting then as static ip address still does not work.

I'm thinking that its a certificate verification problem, but cant find a solution. Any help would be appriciated.

Thanks