[Distutils] PyPI upload: zip okay, tar fails with "invalid distribution file"

[Ethan Furman]

I migrated my split py2/py3 code base into one as I couldn't get setup to do what I wanted, and now I am having this 
problem.

Here's my setup.py:

========================================================================
import sys, os
from distutils.core import setup

long_desc = open('enum/doc/enum.rst').read()

setup( name='enum34',
        version='0.9.1',
        url='https://pypi.python.org/pypi/enum34',
        packages=['enum'],
        package_data={
            'enum' : [
                'LICENSE',
                'README',
                'doc/enum.rst',
                'doc/enum.pdf',
                'test/test_enum.py',
                ]
            },
        license='BSD License',
        description='Python 3.4 Enum backported to 3.3, 3.2, 3.1, 2.7, 2.6, 2.5, and 2.4',
        long_description=long_desc,
        provides=['enum'],
        author='Ethan Furman',
        author_email='ethan at stoneleaf.us',
        classifiers=[
             'Development Status :: 5 - Production/Stable',
             'Intended Audience :: Developers',
             'License :: OSI Approved :: BSD License',
             'Programming Language :: Python',
             'Topic :: Software Development' ],
      )
========================================================================

and an example run:

========================================================================
ethan at media:~/source/enum$ python setup.py sdist --formats tar upload
running sdist
running check
reading manifest template 'MANIFEST.in'
writing manifest file 'MANIFEST'
creating enum34-0.9.1
creating enum34-0.9.1/enum
creating enum34-0.9.1/enum/doc
creating enum34-0.9.1/enum/test
making hard links in enum34-0.9.1...
hard linking LICENSE -> enum34-0.9.1
hard linking README -> enum34-0.9.1
hard linking setup.py -> enum34-0.9.1
hard linking enum/__init__.py -> enum34-0.9.1/enum
hard linking enum/doc/enum.pdf -> enum34-0.9.1/enum/doc
hard linking enum/doc/enum.rst -> enum34-0.9.1/enum/doc
hard linking enum/test/test_enum.py -> enum34-0.9.1/enum/test
Creating tar archive
removing 'enum34-0.9.1' (and everything under it)
running upload
Submitting dist/enum34-0.9.1.tar to http://pypi.python.org/pypi
Upload failed (400): invalid distribution file
========================================================================

Any ideas?

--
~Ethan~