Hi, max,
mad max:is it just changing the file extension?
Now, that would be too easy.
Inside QuarkXPress just "import" the F4V file into a video object via the "External Reference" method (as you woudl with FLV) and export the SWF.
What you need to do next is to change the finally exported SWF file to tell Flash Player, that you are using a newer SWF version. It is a bit risky, as Flash Player will assume it is newer Action Script and interprete all of the code to the new version.
So please use this with care and test your SWF carefully, as it is a completely unsupported hack.
The way you do that:
1. Open the SWF in a binary hex editor.
2. Change the forth byte from 07 to 09.
3. Save.
4. Test well.
Enjoy!
Matthias