Thanks for the reply. However, we were finally able to nail this down as
definitely not being PowerDNS' issue.
The server(s) in question are FreeBSD using the pf firewall. Both servers
are running FreeBSD 8.1, and have nearly identical rules. I copied over
the firewall config from the
Wait, found that this is the same problem as in thread DNS resolution
problem with pdns-recursor-3.3
I am sorry, but I think this has been a wild goose chase regarding a
bug in the recursor. The existing 3.3 version works just fine with
resolving cdn4.digitalconcerthall.com from a system
