I am going to say the problem you are seeing has to do with your firewall or similar device not allowing DNS packets larger than 512.
If you put the following in your conf file you will see that it works fine.
server 0.0.0.0/0 {
edns no;
};
Make sure it is outside of any other clause (for example make sure it's not inside your options or logging clause).
If your using IPv6 then also add:
server ::/0 {
edns no;
};
This will disable edns and keep the packet size down to something more familiar to older firewalls.
Read more here for an overview:
http://en.wikipedia.org/wiki/Extensi...anisms_for_DNS
