title: pip - Requirement already satisfied?
body: <p>pip recognize global installed packages..?!  :-(</p>
  
  <p>I've used virtualenvwrapper preactivate hook to clean PYTHONPATH,</p>
  
  <pre><code>export PYTHONPATH="" 
  </code></pre>
  
  <p>then echo $PYTHONPATH returns empty string, but this didn't help.</p>
  
  <p>What's wrong?</p>
  
  <pre><code>bentzy@lama:~$ mkvirtualenv test
  New python executable in test/bin/python
  Installing setuptools............done.
  Installing pip...............done.
  virtualenvwrapper.user_scripts creating /home/bentzy/.virtualenvs/test/bin/predeactivate
  virtualenvwrapper.user_scripts creating /home/bentzy/.virtualenvs/test/bin/postdeactivate
  virtualenvwrapper.user_scripts creating /home/bentzy/.virtualenvs/test/bin/preactivate
  virtualenvwrapper.user_scripts creating /home/bentzy/.virtualenvs/test/bin/postactivate
  virtualenvwrapper.user_scripts creating /home/bentzy/.virtualenvs/test/bin/get_env_details
  (test)bentzy@lama:~$ which pip
  /home/bentzy/.virtualenvs/test/bin/pip
  (test)bentzy@lama:~$ sudo pip install simplejson
  Requirement already satisfied (use --upgrade to upgrade): simplejson in /usr/lib    /python2.7/dist-packages
  Cleaning up...
  (test)bentzy@lama:~$ echo $PYTHONPATH
  
  (test)bentzy@lama:~$ pip --version
  pip 1.2.1 from /home/bentzy/.virtualenvs/test/lib/python2.7/site-packages/pip-1.2.1-py2.7.egg (python 2.7)
  </code></pre>