cannot login to Snow leopard server open directory from wireless network

I just setup a SL Server with DNS, OD, AFP... if I plug my MBP into the switch then I can login through OD with out any problems. The problem I'm having is when I disconnect from the switch & say go into a different room this time using wireless network I'm unable to login through OD

Now my Airport extreme is setup to be the Nat, DHCP server... I didn't let SL server reconfig it during the setup, only because the Airport Extreme is behind an AT&T uverse RG.

Wondering whats going on... On the airport extreme I did not put in the IP of the server in its DNS... could that be the answer?