title: Creating a new virtualenv hangs
body: <p>I have a macbookpro.</p>
  
  <p>I downloaded virtualenv.py from pylonsbook.com/virutalenv.py</p>
  
  <p>when I type:</p>
  
  <pre><code>python virtualenv.py --no-site-packages env
  </code></pre>
  
  <p>it outputs:</p>
  
  <pre><code>New python executable in env/bin/python
  </code></pre>
  
  <p>then it just hangs, I don't get the prompt in terminal.</p>
  
  <p>I've restarted the computer and I get the same result, what's wrong?</p>