Jeez, did I take long enough to respond? :) The fix suggested on that list didn't help even a little bit. But I found last night when trying to compile nmap that my C compiler was unable to create an executable. Given that my previous attempts to compile modules utilizing C components failed when trying to find the output files from the C compilation, I think the problem was in general an inability to create object files.

In any case, I upgraded my version of Xcode Tools to 1.5 and now everything is working perfectly.