Use of Special Characters in Project Name

Ran to an issues with uStn not creating PDF's because of a comma "," in the project name.  Can someone refresh my memory about the special characters not recognized by Microstation??

In the good old days (Unix, NT, XP) only underscore, dash with letters & numbers were allowed.

Steven W.

Win 10 64bit

SS4 08.11.09.829

V8 08.05.02.70