A nice challange, I spent an age on this and came up with nil.
Finding a swf file first, there are all sorts. I can make one from a panorama image in autopano, spins around but still just a single image not a movie.
Then there is this, http://code.google.com/p/dockableflex/downloads/detail?name=sample%20video%20(beta_r14).swf
a glorified animation.
Looks like the OP has done better and has a swf with a proper embedded video.
Might still be worth looking at edit.py just to get some file information. It is just some python code that will run from 'home' does not go near root.http://www.unixuser.org/~euske/vnc2swf/
Using that google swf
[rich@localhost Videos]$ ./edit.py -o test.flv sample.swf
Using PIL 1.1.7
Input movie: version=4, size=800x600, framerate=25fps, frames=5155, duration=206.2s.
Output movie size: 800x600
Scanning source swf file: sample.swf... 5155 frames written (duration=206.2s)
still does not produce anything workable but at least there is a framerate which might solve the fast mencoder video.
I did try DivXconvertor which is a great front-end for mencoder, error - could not decode the swf. Ffmpeg - no good. Avidemux - no good. It is going to depend on the flavour of the swf.
Came to the conclusion that one way would be to re-record from the monitor using (say) recordmydesktop (although for screen capture I prefer ffmpeg.)