title: Permission problem installing virtualenv on Linux with apt
body: <p>I'm using linux mint 14, and installed virtualenv via apt-get:</p>
  
  <pre><code>$ sudo apt-get install python-virtualenv
  $ virtualenv --version
  &gt; 1.7.1.2
  </code></pre>
  
  <p>The problem is that it's an old version. When I install it via PIP, it installs the version I want, but it is only acessible via root user:</p>
  
  <pre><code>$ pip install virtualenv --upgrade (fails)
  &gt; ...OSError: [Errno 13] Permission denied: '/usr/bin/virtualenv'
  $ sudo pip install virtualenv
  $ virtualenv --version
  &gt; bash: /usr/bin/virtualenv: No such file or directory
  $ sudo virtualenv --version
  &gt; 1.8.4
  </code></pre>
  
  <p>Any hint?</p>