I've found that on our 6.5SP5 server wrong filesystem rights are being
set for few specific users. I have few "problem" users.

Example: I have a problem user "lukas". I set the rights for user
"lukas" to a directory using Novell Client for Windows (4.91SP2),
however after clicking "apply" the rights are assigned to a different
user. That different user is always the same for all "problem" users.

The problems appears on all volumes of that server but on different
NW5.1 server everything works right.

What could be the problem? How do I correct it?