Dhcp Binding Issue

I am running W2k3 as a PDC and it is servicing clients
with DHCP, or at least it was. The DHCP service is running
great, but it stopped binding to the network interface for
no reason. When I navigate to the advanced section of the
DHCP server and try to set the bindings I see the
interface with the correct IP, but when I select it
it "doesn't seem to do it". What I mean by that is when I
select it and say 'OK' everything looks great, but when I
go back to that screen the little box is now unselected.
This is causing the clients to be unable to get a DHCP
lease. I am running them on static leases right now, but I
want this to change. Any suggestions on what might have
caused/be causing this to happen. I have never seen this
happen before. Thanks.

Casey Floyd