So I installed Ubuntu 6.10, and proceeded to install daemontools. Everything worked as usual, I had to fix the errno issue, and voi... huh? svscan didn't start!!
I poked around a bit and found out that Ubuntu has apparently dropped /etc/inittab in favour of /etc/event.d. So /etc/inittab doesn't exist any more, and nothing is done for backwards compatibility. Idiots...
So here's the solution for daemontools. Follow the instructions on http://cr.yp.to/daemontools/install.html. When you are done, create the file /etc/event.d/svscan with this content:
# svscan - daemontools # # This service maintains an svscan process from the point the system is # started until it is shut down again. start on runlevel-1 start on runlevel-2 start on runlevel-3 start on runlevel-4 start on runlevel-5 start on runlevel-6 respawn /command/svscanboot