PF Log:
2009:10:13-16:35:12 post ulogd[8391]: id="2001" severity="info" sys="SecureNet" sub="packetfilter" name="Packet dropped" action="drop" fwrule="60001" seq="0" initf="eth1" outitf="unknown" dstmac="00:xx:yy:zz:xx:5f" srcmac="00:00:00:00:00:00" srcip="68.105.29.12" dstip="[Our Public IP]" proto="17" length="104" tos="0x00" prec="0x00" ttl="60" srcport="53" dstport="64709"
2009:10:13-16:35:13 post ulogd[8391]: id="2001" severity="info" sys="SecureNet" sub="packetfilter" name="Packet dropped" action="drop" fwrule="60001" seq="0" initf="eth1" outitf="unknown" dstmac="00:xx:yy:zz:xx:5f" srcmac="00:00:00:00:00:00" srcip="68.105.28.11" dstip="[Our Public IP]" proto="17" length="104" tos="0x00" prec="0x00" ttl="60" srcport="53" dstport="13778"
68.105.29.12 and 68.105.28.11 have been the forwarders we've used for awhile.
I flushed the cache, removed our internal DNS server (the only item there) from 'Allowed Networks' pressed [Apply], then put it back in. I also deleted the Forwarders, [Apply] and replaced them. This seems to have resolved the issue for the time being.
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