No, I don't think so.
However, that being said: maybe it's an option to convert your subtitles to e.g. .srt format?.
I personally don't know the smil-format. (Are you sure it isn't .smi or sami?) But I could point you to two programms, which primarily are used to sync subtitles, but could also be used to convert subs.
E.g. there is Vladimir's "SubSync". This only covers .smi .srt and/or .sub format subtitles. You can simply load e.g. a sami-file in SubSync and then immediately save it as a subrip .srt file (by changing the filetype into .srt upon saving).
http://users.pandora.be/vlad/subsync/index.htm
Another program, covering many more subtitle formats (though I didn't see .smil in its list) perhaps is (I personally have no experience with it, as I dont use it):
http://viplay.cs-wuzz.com/english/pa...leworkshop.htm