Mac OS X 10.1: Now with extra compiling woes!

[John Siracusa]

Okay, so how soon can we start to talk about the wonders of "two-level
namespaces":
    
http://web.mit.edu/darwin/src/modules/cctools/RelNotes/CompilerTools.html

and the havoc they wreak on previously-working build processes in the
upcoming Mac OS X 10.1?  Perl 5.6.1 built with only minor tweaks on 10.0.x,
but 10.1 throws it for a loop.  Has anyone got the secret formula to make it
work again?

-John