[G4] G4 Processor on a B&W G3 motherboard?

[s*]

Hi, a friend of mine just acquired a Rev2 B&W G3 motherboard.  We are  
going to try and build him a hackintosh using either a PC case or a  
mac case (if we can get our hands on one).  I have the instructions  
from here on how to build one of these:

> http://www.xlr8yourmac.com/systems/MacinPC_ATX_case/ 
> Blue_G3_to_ATX.html

I have an extra G4 400 AGP processor.   does anyone know if it would  
be possible to add this processor to the B&W G3's motherboard?

thanks,

-s*