[Samba] replacing microsoft file server with linux samba server ?

[oystercatcher]

This is a question about microsoft license fees for desktop connections.
If a microsoft file/print server is replaced with with a linux samba server
or if the company starts out with a linux samba server, how would 
the desktop connections be monitored for the purpose of microsoft
collecting connection fees?   When using the linux samba server
is there even a need to consider this scenario?

The reason I ask is that I read about a ms client that continued
to pay desktop connection fees to microsoft after replacing 
a  windows file/print server with linux and samba.   

My small client is currently not on a file server and all their pc's
come from dell so they are properly licensed as desktops.  I
have them networked so that they can share files and assume
up to this point that microsoft does not need to be involved.
After the linux file/print server is installed,  I do not see the 
point of contacting microsoft to offer money for any reason
but I need to ask if anyone knows about this because I
dont want to put my client at risk due to my ignorance.


Thanks