[Distutils] Building a platform-independent dist?

[skip at pobox.com]

It's been several months since I created a distribution using the bdist
command.  Now I can't seem to build a simple gztar distribution.  My
MANIFEST.in looks like this:

    include README RELEASE-NOTES LICENSE MANIFEST
    include lockfile.py setup.py ACKS
    recursive-include doc *.rst conf.py Makefile

MANIFEST is:

    ACKS
    LICENSE
    MANIFEST
    README
    RELEASE-NOTES
    lockfile.py
    setup.py
    doc/glossary.rst
    doc/index.rst
    doc/lockfile.rst

and I'm executing

    python setup.py bdist --formats=gztar

(where python is 2.7a2+).  The output is a .tar.gz file but it includes
".macosx-10.4-i386" in the filename and the tar file itself has more
structure and fewer files than I think it should have:

    % tar tfz dist/lockfile-0.8.macosx-10.4-i386.tar.gz 
    ./
    ./Users/
    ./Users/skip/
    ./Users/skip/local/
    ./Users/skip/local/lib/
    ./Users/skip/local/lib/python2.7/
    ./Users/skip/local/lib/python2.7/site-packages/
    ./Users/skip/local/lib/python2.7/site-packages/lockfile-0.8-py2.7.egg-info
    ./Users/skip/local/lib/python2.7/site-packages/lockfile.py
    ./Users/skip/local/lib/python2.7/site-packages/lockfile.pyc

setup.py is simple:

    from distutils.core import setup
    setup(name='lockfile',
          ... bunch of kwd args elided ...
         )

Where are the missing files?  How do I create a platform-independent
distribution?

-- 
Skip Montanaro - skip at pobox.com - http://www.smontanaro.net/