Problem in HTREE directory node

[Ross Boylan]

Short version: 

fsck said
"invalid HTREE directory inode 635113
(mail/r/user/ross/comp/admin-wheat) clear HTREE index?" To which I
replied Yes.  

What exactly does this mean was corrupted?  In particular, does it mean
the list of files in the directory .../comp/admin-wheat was damaged?  Or
is the trouble in the comp directory?

Is fsck likely to have fixed up things as good as new, or might
something be lost or corrupted?  I don't know what clearing the HTREE
index does.

How can I check if things are OK?  I have backups.



Longer version:

After an ugly but should have been clean shutdown I got reports that
most of my partitions were unclean.  There were a lot of logs replayed.
The partitions are almost all LVM volumes.  My mail spool is ext3, and
fsck showed 
"Problem in HTREE directory inode 635112 node (627) not referenced.
Problem in HTREE directory inode 635112 node (628) has invalid depths
Problem in HTREFsdck died with exit status 4."
The message continued with info on a possible log (which wasn't
there--maybe because I use an initrd?) and need for
manual check.  There were too many messages, about consecutively
numbered nodes, to see them all (always in pairs as above).  628 was
the last.

Manual fsck tells me I can't use auto mode.  Full manual gives
"invalid HTREE directory inode 635113
(mail/r/user/ross/comp/admin-wheat) clear HTREE index?"
I said Yes, and run completed.  Reboot.

Still FS not clean messages for most, and 
"cyrspool primary superblock features different from backup, check
forced."
Finally it starts.

I'm running a Linux 2.6.25 kernel on a P4; that particular partition was
on a SATA disk.  I recently added another SATA disk and added it to the
volume group that included my mail spool.  I have some IDE disks too.

When LVM starts up it gives the error
Parse error at byte 3306 (line253): unexpected token
9 times.  I think it's been doing this for a long time.  It seems to
discover and activate all the volume groups.

So, my main questions are up above ("short version").  I also wonder
why, even after my manual fsck, I got the error about the primary
superblock features differeing.

My more general, and probably harder, question, is how things could have
gotten into this state.

Thanks for any insight.
Ross Boylan