Flutterby™! : AVI to QuickTime?

Back when I knew way more about QuickTime than was healthy, I seem to remember a simple file format converter that would read frames from AVI files and drop the data into a QuickTime file, keeping the codec specifications the same, just repackaging the digital data into the new format. Further research on my video on Linux experiments indicates that if I could find source code for this utility I'd be very happy. I'd write one myself, but I don't want to have to rededicate those neurons if I can avoid it, the details of framing just don't appeal any more... Anyone got any leads?