Comment 92 for bug 462169

I also had this problem of occasional hangs during boot, when networking is configured on ubuntu karmic.
The hangs still occurred, even though I disabled samba via update-rc.d. Found out that samba-related
stuff is called in /etc/dhcp3/dhclient-enter-hooks.d/samba. The following patch may be related:

http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=572483

See also:
http://ubuntuforums.org/showthread.php?t=1382776
https://bugs.launchpad.net/ubuntu/+source/samba/+bug/462169