partimage and devfs

[Martin <martin@marijg.demon.nl>]

Hello,

I use partimage for some time. And now I have a new Sarge intallation in a 
clean partition. I want to back-up a other partition as I am used to do.
But noew I get the following warnig when i start partimage:

You have devfs enabled but not mounted. Yoe have to do it to continue. You can 
also boot with non-devfs kernel if you have one.

I do not know what devfs is. I cannot find devfs in the manpages of partimage 
and mount.
Can someone give the idea I need ?

Greetings,
Martin