I have implemented an uninstall option. If you specify -c or --create-uninstall to the install command, an uninstall script named <package name>_uninstall.py will be built and it will be installed in install-lib resp. install-platlib. To uninstall your package, execute this script with python.
Note that the uninstall option requires you to supply a package name in setup.py.
The patch is against the latest CVS snapshot.