Help with subtitles

[petsnspace]

I have a question that searching didn't really find a good answer. When I want to watch a movie on my iPhone, I use DVD fab to rip the movie and then handbrake to convert it. All is well, unless it is a foreign film with subtitles. When I use DVD FAB, it appears to pick up the subtitle track and handbrake recognizes it when converting. When I play it in iTunes or iPhone, it doesn't appear.

Am I missing a simple step or does the iPhone and iTunes have difficulty with subtitles. Any help is appreciated.