Dear slackers, I have no idea what the solution to my problem might be,
so I turn to you. The short of it is that I can no longer su to root.
If I run su I get the following output:

~$ su
Password:
Sorry.
~$

I still am able to log in as root, so I think something must be wrong
with my own useraccount, but I don't know what. I did not forget root's
password, in any case.

Likewise, I have also become unable to mount my iPod, which formerly I
could. Root can still mount it, fstab formerly said, and still says

/dev/ipod /mnt/ipod vfat noauto,defaults,gid=100,user

but I can't.

I googled about the su issue, but the only fix I saw concerned the
permissions for su, and they are correct on my box (I checked against
the package from which it originated).

Now, what I'm looking for is a way to fix my user-acount, so that I'm
able to su again, and so that I can mount partitions which users should
be able to mount again.

To clarify, all this happened after I made some changes to my
partitions. It's a long story so I'll only mention what I think is most
important. I have Slackware 10.1 installed on two Reiserfs partitions,
one for / and one for /home. Among other things,

(1) I added a partition, which effectively moved Slackware from
/dev/hda8 and /dev/hda9 to /dev/hda9 and /dev/hda10 (and afterwards
changed fstab accordingly, reinstalled grub to the boot record of root,
etcetera; I re-installed grub many times, I load it from ntldr, the
winXP boot manager).

(2) I imaged, restored, shrinked and then enlarged my root partition (in
that order, to counter some unexpected side-effects of restoring an
image to a larger partition), after which reiserfsck prompted my to run
with the option --rebuild-tree. After that I was able to login as root
again, and for root everything seemed to work fine.

(3) I imaged and restored my /home-partition, and then zipped (to a
fat-drive) and unzipped the /home/'my account'-folder.

Somewhere I must have done something wrong, but I don't know what, or
what might have changed. I did check the file-permissions in my
home-folder, but all files seem to be owned by me, and group users, so
I'd say nothing's wrong there. I also erased all temp-files that were
associated with my user-account, but to no avail.

Well, I hope you have some further ideas to solve this. If this is the
wrong place for my question I'll check elsewhere, just tell me.

Regards,
PJ