IPv6 under Linux 2.6 seems to kill name resolution
Since some time I've been wondering why name resolution under my 2.6 box was so slow. I even set up a local caching-only nameserver and it didn't helped at all.
Today, after I read Jeremy Wells review of Ubuntu on OSnews I gave his tip on ipv6 module loading prevention a try. Woo ! Now name resolution is working again at the same level it should be always working.
I already did it to my two home machines (my router and my laptop) and now they are much better to work with when it comes to name resolution (i.e. always for me).
In time : I'm using Debian unstable, not Ubuntu.