I'm using Tunnelblick (an OpenVPN wrapper) to establish a VPN connection on my MBP running Snow Leopard. The connection is great, and was giving me no trouble at all for several months. The VPN provides its own private DNS server to resolve names within the VPN and related operations.
I've recently moved, and while my VPN configuration and local network environment haven't changed at all, I've now acquired a most infuriating problem: name resolution for those names provided by the private DNS server has become intermittent. Literally, one second I can resolve a particular name fine, the next, I can't. I've not discovered a pattern to the intermittency.
dscacheutil -flushcache doesn't seem to affect the matter one way or the other much, though occasionally it does help immediately and unaccountably.
I'm at my wit's end on this. Any idea what's going on?