One of our machines has to remain at RedHat 7.3 and crashed it's disk.
With one of SL LiveCD's I was able to restore everything.
During boot I received a message like
fsck.ext3: Filesystem has unsupported features
e2fsck: Get a newer version of e2fsck
and fails to mount.
It has e2fsprogs-1.27-3 but since it cannot boot I cannot upgrade.
With debugfs I checked and removed some features but I could not get it g
oing.
It appears that something changed in ext3 that makes it not backwards
compatible. Maybe an SL3 LiveCD could help but that seems not available.