title: PHP decode GB2312
body: <p>I'm working on an IMAP email script and I have some lines coded in <a href="http://en.wikipedia.org/wiki/GB_2312" rel="nofollow">GB2312</a> (which I assume is Chinese encoding), looks like this <code>=?GB2312?B?foobarbazetc</code></p>
  
  <p>How can I start working with this string?  I checked <code>mb_list_encodings()</code> and this one is not listed.</p>