title: Recovery of the hash avatar on XMPP for facebook
body: <p>I am using asmack as XMPP client for Facebook chat. I have a small problem with the recovery of 'hash of the avatar.
  Vcard and Presence release a different hash for the same photo.</p>
  
  <p>presence releases this fragment xml:</p>
  
  <pre><code>&lt;presence to="-1397017951@chat.facebook.com/Simple Chat for facebook_9f178c85_4DFBAD2D51CCA" 
      from="-100001386664684@chat.facebook.com"&gt;
          &lt;x xmlns="vcard-temp:x:update"&gt;
              &lt;photo&gt;4315d3952f68dcc09fe5e2c656e7d73707d950ec&lt;/photo&gt;
          &lt;/x&gt;
  &lt;/presence&gt;
  </code></pre>
  
  <p>While using the vCard object is issued a different hash:
  <strong>4e935a5e328ddd204f08d4d7159712accaada491</strong></p>
  
  <p>The avatar is the same
  How come? I have to do some other operation to obtain the same hash?</p>