G5 C++ Development using g++/XCode

Hello,
I have been developing a cross platform application written in C++.
This product uses Xcode/g++ on the Mac side, and VS.Net C++ on the Windoze
side.

I currently have a G4 900 Mhz. single processor machine.
It takes me two hours to to a full recompile and link of all my
libraries and programs.

I need a faster machine. I am looking to buy a new G5 dual processor
system.

Does anyone know if the Xcode developer tools make effective use of
the dual processor G5 technology?

What would you folks recommend for a C++ development system
in terms of (Single/Dual processor) and Memory?

Thanks,
Paul
PKF Systems