Use local lang file

Hi, I'm writing a chessclient, and I'd like to have syntax highlighting
on pgn, which is a chess format.

I've written a lang file, but I don't think the format is common enough
(for non chess players) to be included in gtksourceview. Rather I'd like
just to pack it with my application, and tell gtksourceview to use the
file instead of any /usr/share/gtksourceview-1.0/language-specs/ file.

Is this possible? I haven't been able to find any methods on
http://www.pygtk.org/pygtksourceview/index.html (writing in python)

-- 
Med venlig hilsen,
Best regards,
Thomas