Thanks again. It appears a combination of "Subtitle Workshop" (http://www.urusoft.net/downloads.php?lang=1) and "Auto Gordian Knot" (http://www.autogk.me.uk/) should do the trick (http://blog.proud-geek.com/2007/05/17/captioning-your-videos-3-subtitle-workshop/ and http://jarednevans.typepad.com/blog/2007/01/auto_gordian_kn.html).
