Please help with a closed caption or subs solution!

Question

Hi all,
I have been reading up on the various methods of including cc or subs with QT movies but am still a bit stumped as to the best solution for my situation.
We have a desktop application that allows customers to purchase educational videos through branded client catalogs. The videos are downloaded to the customer's Mac or PC and then play back, within our program, utilizing QT player (and we also have the option to switch to MPlayer for older PCs).
Our clients have begun asking if they can also offer alternate versions of their videos with subtitles in various languages. My first thought was this would be a snap, just by adding properly-named and formatted .srt files to the proper directories, and while it seems like this will work if they are using MPlayer, the vast majority of our customers are using QT. Is there a type of text file we can have our clients supply us with that will work automatically in this sense? If not, is there any sort of command-line client we might be able to use to quickly and easily mux mp4 files with cc or subs?
The key here is simplicity, and ideally we would really like to not have to have multiple versions of the mp4s themselves, just having various cc or sub txt files would make everything so much easier!
Is this possible? Am I totally missing an obvious solution?
Thanks so much for any help you can offer!
Best,
Jeff

Answer 1

http://www.macosxhints.com/article.php?story=20071103080237904
http://forums.macrumors.com/showthread.php?t=282408
NicePlayer mentions subtitle support in the help menu