While reading the sample http://slackware.osuosl.org/slackware-11.0/extra/udev-alternate-versions/rc.S, I found this thing here:
INteresting, as such you would have to change lines in /etc/lilo.conf and not in rc.S
Hope this somehow helps solve the problem. I don't use slackware and this is interesting though :) Goodluck
I think this is a lilo issue and try a question about lilo and mounting at stackoverflow (I'm not sure of slackware users here though)..
answered May 30 '10 at 08:35