HD Install :: grub boot code problem

I recently switched from a lilo boot to a grub boot on the same machine using a frugal hd install. I have the following grub menu.lst:

Quote

title dsl-3.x
root (hd1,2)
kernel /boot/linux24 root=/dev/sdb3 dsl lang=us vga=773 apm=power-off nomce nodma quiet frugal mydsl=sdb4 restore=sdb4 toram alsa syslog
initrd /boot/minirt24.gz
boot

The back up is restored from sdb4 but no extensions in /mnt/sdb4/mydsl are loaded. Any idea what the problem might be? - I've tried mydsl=/dev/sdb4, /mnt/sdb4, /mnt/sdb4/mydsl, etc.

I think I've seen =sdb4/mydsl used before. Don't know if it applies to 3.x or 4.x (or none)

original here.