I just tried to build and install a distutils package using Python 1.5.2. The package uses some features added after 1.5.2 and a few files have SyntaxErrors as a result. I did a "setup.py build" and didn't get any complaints, but I did get errors when I tried the install.
Does setup.py build generate .pyc files? It seems like it must not, or I should have seen errors when I did the build. If it doesn't, it seems like it should; otherwise you'll fail to catch SyntaxErrors until install time.