truncated 3GP MOV and MP4

[blah789]

Does anyone know of methods to recover truncated 3GP MOV and MP4 files? It's supposedly difficult because the header is at the end of the file as opposed to the beginning like in AVI or MPEG-1 or MPEG-2.

The aim is to recover truncated 3gp, mov, and mp4 as would be downloaded from a digital camera or cell phone. (should be easier since you can get produce other samples)

I had some ideas I'd tried before
http://www.moviecodec.com/topics/8907p1.html (for AVI - head transplant surgery - I wrote those steps and use it quite a bit to recover AVI files from digital cameras with missing headers because it's easy to get a working sample - almost always MJPG and regular resolutions (QQVGA, QVGA, VGA) and regular frame rates (15 30 sometimes 60 10 or 20 too) - if anyone knows of an automated tool for this let me know).

I tried that "trick" (well replaced "footers" of varying length - making sure the moov string was in there) on mp4 and 3gp without success though:
http://www.moviecodec.com/topics/60009p1.html (with actual samples)
http://www.moviecodec.com/topics/49950p1.html

but that's probably because I can't figure out how much of the footer information goes in, what it means (like does it have to be of correct size? or must frame rate/res match? can you artificially input file size? AVI tends to ignore size with players smarter than WMP).

So yeah, anyone know anything about this?