DNS Problem

We have turned on Packet filtering on our WEB/DNS/Proxy Server and now we cannot access the site by DNS name only IP. I have entered the BOTH UDP DNS entry into the Packet Filter Exceptions list. There are two other sites that this box does DNS for that are now unreachable by DNS. E-mail for these domains will not get resolved either.

This is a WINNT4 SP6a box with Proxy 2.0 SP2 and IIS4