samba - Apr 2004 - migrating froma win2k PDC server to samba

I want to use a linux server as pdc for a windows network. 

I create users, profiles, etc.. on smbpasswd and on unix database,  and
the xp-pro  and win-98 machines joins the domain well. 

But the win2k machines doesn't works. 

So:
I extracted from the window server the win2k accounts (differents from
the win98 accounts) and the sid. How can i use them on the linux server
?   

I don't want to migrate old profiles, I just want that old users logs on
the new server.  

There is another little matter: a system has a machine name
"Server-Uni"
and a username "Server-uni" , different only by the case... This is a
matter on translating the accounts ? 

thanks 
Enrico Betti