Obtaining IP Address via DHCP

Here is a brief description of my configuration:
Windows 2003 DC server with AD
Windows 2000 member Server acting as internal router and DHCP server
LinkSys WAP54G access point
Dell Axim X50

Originally my servers were Windows NT 4.0. I could obtain an IP address on
my X50 and browse network resources and the internet. I upgraded the
servers to Server2003 and registered the DHCP server as authorized. Now my
wireless client cannot obtain an IP Address to access the network. My wired
clients are having no problems.

I have a feeling my problem has to do with the way Active Directory handles
DHC authorization. Can someone point me the right direction?

Thanks.
Eric.