I just added support for installing grml on software RAID level 1 with grml2hd. As we already have support for initrds it wasn't such a big deal. [Disclaimer: it's not a frontend for mdadm, you have to use mdadm manually on your own. If you want to use software RAID you should know how to handle it anyway.]
So if you want to use RAID1 with '/' on software-raid run mdadm and install grml afterwards on the new created device using the environment variable SWRAID which passes the provided option to the raid-extra-boot-option in lilo.conf:
# mdadm --create --verbose /dev/md0 --level=raid1 \
--raid-devices=2 /dev/hda1 /dev/hdc1
# SWRAID='mbr-only' grml2hd /dev/md0 -mbr /dev/md0
That's it. :-)
