soverlay with dvb-subtitles.

[keppis]

I've noticed that I am able to watch dvb-subtitles with vlc correctly - but the soverlay option does not work and I cannot burn the subtitles to the transcoded video. I do have tested this with ts files from YLE TV1 terrestial transmission which do include both teletext and dvb-subtitles. I am able to view them both on playing mode, but only teletext subtitles can be soverlayed during transcode.