[ILUG] compiling an X Driver

[nils]

hi,
Can anyone tell me how to compile an X driver (sis_drv.o)for xFree4.2, i 
have the source code and have a binary for xfree86 4.1.0 but i want to 
be able to have GLX enabled.
1. I need the Xfree86 source
2. Where do i put the source code
3. How do i apply a patch to a Makefile,it 
Makefile4.1-->Makefile4.2patch === Makefile4.2
I have looked on linuxdoc.org for any howtoo's but their were none!
Any ideas
Nils