I've reverted the change to move from distutils to setuptools in
setup.py for the release. Reason was that the release instructions in
BUILD.txt no longer worked. In particular the --manifest-only option in::

  python setup.py sdist --manifest-only

didn't work anymore. Since setuptools with the sdist command didn't
create a MANIFEST file and since I don't know how setuptools selects the
files to package I've reverted the change.

Do you know how to fix this? Is there a mechanism different from a
MANIFEST file that is used by setuptools? Or can it be configured to be
backward compatible to distutils?

Thanks for your help.
Ralf