Mozilla XCode Command Line Parameter Help

I have XCode setup to build all intermediate files to a directory
called Intermediate, and all final products to a directory called
Runtime.

When I build Mozilla, it uses XCode to compiled Default Plugin.plugin
and PDEPlugin.plugin.  Mozilla isn't looking in the Runtime or
Intermediate directory, and freaks out.

I updated my XCode settings, and Mozilla builds fine - but this is a
global setting and affects my other projects.  I could tweak the
Mozilla makefiles to look in these directories, but this seems klunky
as I might want to copy my Mozilla tree to another, different system.

Is there a way to pass a command line parameter to XCode which tells it
where to put intermediate and compiled binary files?

Thanks in advance,
Pete