I have a problem with a ubuntu-10.4 VM. When I try to resolve a hostname (using for example nslookup or firefox), my DNS server receive an UDP packet with a DNS query (I saw it with tcpdump), but it drop the request. I tried with a Windows DNS server and a Red Hat DNS server: they receive the query but give no answer. I'm shure that at the end of the installation the name resolution worked !
I have another linux VM: the same query get a response. Comparing requests with tcpdump and wireshark I found no differences between them.