Nonviewable mp4

I've tried making a mp4 without managing to get it playable. I started with an XviD of 'The Phantom', aac'd the sound track using aacenc from rarewares without -adif. Using mp4creator, I -create'd a mp4, interleaved the aac and the file plays fine in mp4player, apart from breaking up a little while after seeking. RealOne plays the file fine, but doesn't show the video and QT6 just crashes (QT plays a mp4 with just the aac in it fine, though). Adding hints and/or optimizing the file doesn't help. What else can I do with it? Otherwise I'm rather impressed; after all, it is the "next" MPEG and f.ex. the muxing overhead (w/o hints) are even lower than ogg, so I'd like to get it working.

According to MPEG4IP team, currently XviD it's not fully MPEG-4 ISO compliant and may lead to compatibility problems with some players such as QT6. You can try to encode switching on B-frames and using max B-frames = -1, this has been reported to fix the issue. You can also try DivX 5. Hope the XviD team solves the issues as soon as possible, ISO compatibility is a 1st class requirement for any modern CODEC IMHO.

Ah, will try. Re. last statement: Indeed, that goes without saying.