[Samba] License question

[Davide Dozza]

I have a doubt.
In my network I have a NT4 working as PDC that authenticates users 
accessing to the network. No other services, file or print sharings, are 
present on the server.
All file and print sharings are available on a Samba server running 
winbind and partecipating to the domain.
PC clients can be Windoze and Linux and all users are registered into 
the PDC.
Questions are: if I don't access to file and print sharing on PDC, 
should I pay the Micros*ft network connection license?
What are the case I have or not to pay such licence?
Are there some schema that helps to understand where and when
Micros*ft licenses are appliable?

Davide