@davidep
It’s not a Linux Samba client. It’s the NS itself.
OK, the original issue I was thinking of may be a non-issue after all.
I need to do a little more checking on this.
But, another problem caused by mixing case showed up when my wife tried to play some of her music, which would lead to more problems (for me) than anything I might find. 
iTunes runs on a Windows machine, but the music itself is stored on an array within NS, in a base directory: iTunes. We have created a large number of playlists that can be sent to an application running on NS that streams the music. These continue to work, as they were built prior to switching to NS. However, since switching, the library on the Windows side is now itunes, after switching the Windows iTunes to use the new share, because of the NS case restrictions. This means any new playlists created, by a COM based application will put itunes as the directory, which will fail when shipped to NS as that is case sensitive.
Renaming the library won’t work, because then all the original playlists will fail. I guess the temporary answer, is to use a couple of soft links to match everything up, but this is just a workaround for what I see is an arbitrary restriction in NS. Unless there is a fundamental reason why mixed case cannot work.
BTW There are some Windows programs, well at least one, made by Apple that is case sensitive on Windows. I tried to fool it con continue to store iTunes as the directory even though the share is itunes. But no, take a look at this screenshot. (Is there a way to embed these in a post. I couldn’t see one).
Cheers.