How can I recover my superblock?

["Glenn Evanish" <glenn@example.com>]

I should have known better, but I just tried to use Partition Magic 6 to
resize partitions on a hard disk that had Linux on it.  It froze in the
middle of a move and I had to switch off the power to kill it.  I was afraid
I'd lost
everything, but Windows and one installation of Linux booted.  My favorite
installation of Linux, though, dropped me into a shell on boot-up and
suggested I run e2fsck -b 8193 /dev/hda10.  I did, but it told me I had a
zero length partition.  I can still cd around the installation from the
shell and see that
everything's there, but I don't know how I can get it to boot through to a
regular log-in prompt.

How can I restore the superblock on a Linux partition?  Do an "upgrade"
installation into the partition and make a cosmetic change or two?  Will
that rewrite it?  Or use a rescue disk?

TIA,

Glenn Evanish