Only hack cmd.library_dirs when running under Py_ENABLE_SHARED.  Tested both with and without --enable-shared on Ubuntu 10.10.  Hopefully this finally solves bug 10126.  Will check 3.1 and py3k next.
Only hack cmd.library_dirs when running under Py_ENABLE_SHARED.  Tested both
with and without --enable-shared on Ubuntu 10.10.  Hopefully this finally
solves bug 10126.  Will check 3.1 and py3k next.

pypa/setuptools,pypa/setuptools,pypa/setuptools