Error unmounting the floppy - "/usr/bin/pumount" (Permission denied)

[agenteo]

Sometimes I miss that we are running a GNU/Linux system.
All of the problems we have it's our fault... or at least most of them :-)
And most of the errors we get, contain the answers to the problem.

Impossible to execute the child process "/usr/bin/pumount" (Permission
denied)

Checking the permissions was the first think to do :-) It's awesome I 
haven't.
ls -l /usr/bin/pumount
-rwsr-x---    1 root     root        12632 2004-11-24 14:04 /usr/bin/pumount

Now all is clear. Some days ago I've moved the /usr from the unique 
partition to a new partition. I've done this from a Knoppix using cp 
/mnt/hda7/usr /mnt/hda8

All the ownership are gone.

I am very happy :-\

Someone can give me a suggestion, can I handle the /usr ? Can I restore 
in someway  the ownerships? Maybe I will just reinstall everything :-)

Thanks,
Enrico