title: Why do I get "unable to connect a socket" when I try to clone via a git URL?
body: <p>When I try to clone a project from the GitHub, it gives me the following error. </p>
  
  <pre><code>:git clone git://github.com/project.git
  github.com[0: 207.97.227.239]: errno=Connection refused
  fatal: unable to connect a socket (Connection refused)
  </code></pre>
  
  <p>But if I use the corresponding HTTP URL, it's fine:</p>
  
  <pre><code>:git clone http://github.com/project.git
  </code></pre>
  
  <p>What should I to do to clone through a git URL?</p>