Corrupt eggs in mailman-3.0.0a6.tar.gz

Following up on this thread:
http://www.mail-archive.com/mailman-developers%40python.org/msg12023.html

I can reproduce the problem:
[cp ~/local/src/mailman-3.0.0a6] ./bin/buildout
Traceback (most recent call last):
  File "./bin/buildout", line 17, in <module>
    import zc.buildout.buildout
ImportError: No module named zc.buildout.buildout

The eggs/zc-buildout* directory is missing the *.py files. Similarly, the z3c.recipe.sphinxdox and zc.recipe.egg.

In the end, I removed the eggs/ directory completely, and got much further down the road. (I am new to eggs, so I am not sure this is the best idea.)

Now, installation seems to fail at the logilab-common step.

Develop: '/home/phil/local/src/mailman-3.0.0a6/.'
Page at http://pypi.python.org/simple/argparse/ links to .py file(s) without version info; an index scan is required.
Uninstalling filetemplates.
Updating docs.
Generated script '/home/phil/local/src/mailman-3.0.0a6/bin/docs'.
Installing filetemplates.
Updating interpreter.
Installing pylint.
Getting distribution for 'logilab-common>=0.50.1'.
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/home/phil/local/src/mailman-3.0.0a6/eggs/setuptools-0.6c12dev_r85190-py2.6.egg/setuptools/command/easy_install.py", line 1712, in main
    with_ei_usage(lambda:
  File "/home/phil/local/src/mailman-3.0.0a6/eggs/setuptools-0.6c12dev_r85190-py2.6.egg/setuptools/command/easy_install.py", line 1700, in with_ei_usage
    return f()
  File "/home/phil/local/src/mailman-3.0.0a6/eggs/setuptools-0.6c12dev_r85190-py2.6.egg/setuptools/command/easy_install.py", line 1716, in <lambda>
    distclass=DistributionWithoutHelpCommands, **kw
  File "/usr/lib/python2.6/distutils/core.py", line 152, in setup
    dist.run_commands()
  File "/usr/lib/python2.6/distutils/dist.py", line 975, in run_commands
    self.run_command(cmd)
  File "/usr/lib/python2.6/distutils/dist.py", line 995, in run_command
    cmd_obj.run()
  File "/home/phil/local/src/mailman-3.0.0a6/eggs/setuptools-0.6c12dev_r85190-py2.6.egg/setuptools/command/easy_install.py", line 211, in run
    self.easy_install(spec, not self.no_deps)
  File "/home/phil/local/src/mailman-3.0.0a6/eggs/setuptools-0.6c12dev_r85190-py2.6.egg/setuptools/command/easy_install.py", line 427, in easy_install
    return self.install_item(None, spec, tmpdir, deps, True)
  File "/home/phil/local/src/mailman-3.0.0a6/eggs/setuptools-0.6c12dev_r85190-py2.6.egg/setuptools/command/easy_install.py", line 476, in install_item
    dists = self.install_eggs(spec, download, tmpdir)
  File "/home/phil/local/src/mailman-3.0.0a6/eggs/setuptools-0.6c12dev_r85190-py2.6.egg/setuptools/command/easy_install.py", line 626, in install_eggs
    unpack_archive(dist_filename, tmpdir, self.unpack_progress)
  File "/home/phil/local/src/mailman-3.0.0a6/eggs/setuptools-0.6c12dev_r85190-py2.6.egg/setuptools/archive_util.py", line 67, in unpack_archive
    driver(filename, extract_dir, progress_filter)
  File "/home/phil/local/src/mailman-3.0.0a6/eggs/setuptools-0.6c12dev_r85190-py2.6.egg/setuptools/archive_util.py", line 188, in unpack_tarfile
    while member.islnk() or member.issym():
AttributeError: 'NoneType' object has no attribute 'islnk'
An error occurred when trying to install logilab-common 0.52.0. Look above this message for any errors that were output by easy_install.
While:
  Installing pylint.
  Getting distribution for 'logilab-common>=0.50.1'.
Error: Couldn't install: logilab-common 0.52.0

Let me know what else I can send you in regards to my environment. I am running a fairly fresh Ubuntu-10.04.1 with Python 2.6.