Stripe Subtitle Fade In and Out Issue

After upgrading to iMovie HD 6, I found the Stripe Subtitle to fade in correctly, but when it begins to fade out, it will abrubtly disappear. In iMovie HD 5, the Stripe Subtitle would fade in and out smoothly. It does this when I preview a stripe subtitle, as well as in finished DVDs and Quicktime movies. I have tried adjusting the speed and pause, but that has no effect on this issue.

You can see an example of this in one of my videos. Just watch the first minute and you'll see it happen when I introduce the first speaker:

http://homepage.mac.com/jasonellis/iMovieTheater5.html

Has anyone else seen this behavior? Does anyone know of a work around?