try something like this:
Code:
[subtitles]
Sub1=French|my_fr_subs_file
Sub2=English|my_en_subs_file
Sub3=Whatever|my_we_subs_file
DefaultSub=0
by the way you'll find everything you need to know (well at least most things you need to know ;)) in c:\program files\bsplayer\doc\ini_files.html