On Wed, Dec 14, 2011 at 09:50:46PM +0100, Giovanni Campagna wrote: Yeah, you've rightly assigned blame to setuptools here. What's happening is that TurboGears1 uses an old version of cherrypy. We have packaged this using setuptools multiple versioning. But setuptools doesn't really have a method of specifying a default version when doing this. That's the source of the error. In order to work around it there are several recipes. The most production quality is to put code like the following as close to the very top of the script that is originally run as possible:: import __main__ if hasattr('__requires__', __main__): if isinstance(__main__.__requires__, basestring): __main__.__requires__ = [__main__.__requires__] else: __main__.__requires__ = list(__main__.__requires__) else: __main__.__requires__ = [] __main__.__requires__.append('TurboGears[sqlalchemy]') import pkg_resources This will work as long as we do this before pkg_resources is imported for the first time. If pkg_resources has already been imported then it's too late. You'll need to get this block of code to execute sooner. Another way that works fine in testing but isn't as portable in production is to specify the path to the proper cherrypy module. On Fedora16 this should look like: $ export PYTHONPATH='/usr/lib/python2.7/site-packages/CherryPy-2.3.0-py2.7.egg $ paver egg_info -Toshio