I think you can only do it using a Flash decompiler.
Alternatively, just like loopback recording a WAV, try
CamStudio 2.0, the "last freeware version" before it was butchered into registerware (2.1 version) by EHELP, and subsequently dropped!
Not sure if it'll work for EXE versions, but it certainly works for in-browser SWF.
You capture the portion of the screen where it's playing - ideally you scale/crop the window so that no further adjustment is needed, and capture it as video.
You need a powerful processor to pull this trick off, as the overheads are enormous - my old Athlon 1200 was too weak, but my new P4 probably will - hyperthreading should also help.
It's a kludge, but it's free!