[Fedora-packaging] How to build SRPMs for Rawhide from Fedora 12

[Edmon Begoli]

Hi,

I am working on a Fedora 12 machine, but I would like to build Java
packages for rawhide
without necessarily enabling rawhide repository for all the system (it
messes with the stable updates).

How can I create an RPM build environment for rpmbuild that accesses
all the dependencies available
in rawhide without affecting the host?

Thank you in advance.
EB