problems playing avi with .sub + .idx subtitles (vlc 0.9.8a)

[polgara]

hi,
I just downloaded vlc 0.9.8a and tried to watch an avi files with subtitles .sub + .idx but it doesn't work: I can see the movie but I don't see any subtitle.

Infos:
- .avi, .sub, .idx files are in the same directory
- opening menu Video - Subtitles Tracks (I see it in italian, hope translation is right) I see 5 tracks but no matter what I select it still doesn't work
- I tried MPUI (Media Player for Windows) and it works: I can see subtitles (so I suppose subtitles files aren't corrupted)
- just in case you need to know, I use WinXP Sp2 (actually I don't think it's a matter of s.o. so I didn't post this in the Windows specific forum. If i was wrong I apologize)

Thanks to anyone who will answer

polgara