bad superblock



I think I got a bad superblock on one of my lvm partiions. First the system
is rhel 4 wont get past grub

it hangs on <GRUB> prompt

I am using the knoppix cd utility. I can get it but cannot mount /dev/sda5
which seems to be where /boot is. I have tried e2fsck, fsck etc and nothing
works. what do I do?


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