I add some captions to .mov file using Quicktime Pro for Windows and the recommended procedure off of the quicktime user guide. After adding the captions in a new text track and save the move as a self-contained movie everything plays/works on my PC just fine.

Problem is if I try to convert it to .flv format using Riva or another program I found called Any Video Converter (the latter worked, but Riva had a hard time with my h.264 file for some reason), then the text track is apparently stripped away and lost. That is, the captions or text I added don't show up anymore in the flash video. This happens even if I directly upload to youtube or viddler, where I assume they are reencoding to flv anyway on their servers.

Any ideas why my captions are stripped away? If I use quicktime pro to first convert to another format (such as .avi or mp4) the captions stay but I lose some of the quality and the ability to keep it in the 16:9 ratio.