Import Image sequence can't handle sequences longer than 15000 frames

[Todd Hiers]

Using the import image sequence feature, I import 777 .svg files and set each to a duration of 30 frames. I overlay this sequence on top of an AVC video and export. The output video works as expected for the first 15,000 frames (500 of the svg files, or 8:20 @ 30fps) and then the svg overlay simply disappears, leaving only the original AVC video for the remainder of the time.