Fails to build with recent setuptools 3.0.2 release

Created originally on Bitbucket by dangra (Daniel Graña)

Easily reproducible with:

#!shell

~$ mkvirtualenv setup3
New python executable in /home/daniel/envs/setup3/bin/python2
Also creating executable in /home/daniel/envs/setup3/bin/python
Installing setuptools, pip...done.

setup3 ~$ pip install -U setuptools 
Downloading/unpacking setuptools from https://pypi.python.org/packages/3.4/s/setuptools/setuptools-3.0.2-py2.py3-none-any.whl#md5=5cfb768ab61350024f22df2c7317077b
  Downloading setuptools-3.0.2-py2.py3-none-any.whl (538kB): 538kB downloaded
  Storing download in cache at ./.pip_download_cache/https%3A%2F%2Fpypi.python.org%2Fpackages%2F3.4%2Fs%2Fsetuptools%2Fsetuptools-3.0.2-py2.py3-none-any.whl
Installing collected packages: setuptools
  Found existing installation: setuptools 2.1
    Uninstalling setuptools:
      Successfully uninstalled setuptools
Successfully installed setuptools
Cleaning up...

setup3 ~$ pip install -U pip
Downloading/unpacking pip from https://pypi.python.org/packages/py2.py3/p/pip/pip-1.5.4-py2.py3-none-any.whl#md5=f20bc8f31e322375ce06b26d73ce7b4f
  Using download cache from /home/daniel/.pip_download_cache/https%3A%2F%2Fpypi.python.org%2Fpackages%2Fpy2.py3%2Fp%2Fpip%2Fpip-1.5.4-py2.py3-none-any.whl
Installing collected packages: pip
  Found existing installation: pip 1.5.2
    Uninstalling pip:
      Successfully uninstalled pip
Successfully installed pip
Cleaning up...

setup3 ~$ pip install cffi
Downloading/unpacking cffi
  Using download cache from /home/daniel/.pip_download_cache/https%3A%2F%2Fpypi.python.org%2Fpackages%2Fsource%2Fc%2Fcffi%2Fcffi-0.8.1.tar.gz
  Running setup.py (path:/home/daniel/envs/setup3/build/cffi/setup.py) egg_info for package cffi
    Traceback (most recent call last):
      File "<string>", line 17, in <module>
      File "/home/daniel/envs/setup3/build/cffi/setup.py", line 94, in <module>
        from setuptools import setup, Feature, Extension
    ImportError: cannot import name Feature
    Complete output from command python setup.py egg_info:
    Traceback (most recent call last):

  File "<string>", line 17, in <module>

  File "/home/daniel/envs/setup3/build/cffi/setup.py", line 94, in <module>

    from setuptools import setup, Feature, Extension

ImportError: cannot import name Feature

----------------------------------------
Cleaning up...
Command python setup.py egg_info failed with error code 1 in /home/daniel/envs/setup3/build/cffi
Storing debug log for failure in /home/daniel/.pip/pip.log