After looooooooooong work Novell finally solved my problems with
user based printers and roaming profiles.

For those who suffer from the same problems, here is what we have
1. Installed Microsoft Hotfix Q812503
2. Installed 483psp2d (be aware that this fix breaks some GPOs from
ZenWorks, like Desktop Settings)
3. Used Spoolsv.exe from W2K SP4
4. Installed iPrint Client 2.01 (from NW6.5 Beta)

Last problem is that some non WHQL certified printers still break
profiles, but once the driver has been installed once on the console,
problem is gone on that specific server.

Hope this information is usefull for some others suffering under the
problems like i did for weeks.