Long story.. ;)
I'm experimenting with grml-live and different boot methods (grub2, isolinux) to create a custom 
rescue image. We don't have dhcp, so a script creates an appropriate /etc/network/interface, but 
that will be overwritten if 'nonetworking' isn't set. According to [1] and with grub2 boot 
method, this works => networking is set up correctly, and dns is set, too. If I choose 
'isolinux' boot method, dns is gone. Don't know what should be the right behaviour

[1] http://git.grml.org/?p=grml-live.git;a=blob_plain;f=templates/GRML/grml-
cheatcodes.txt;hb=HEAD