title: Error in OAuth dialog
body: <p>When I redirect the user on </p>
  
  <pre><code>https://www.facebook.com/dialog/oauth?
    client_id=" + APP_ID +
    &amp;redirect_uri=" + CALLBACK_URL +
    &amp;scope=" + "read_mailbox" +
    &amp;state=" + java.util.UUID.randomUUID();
  </code></pre>
  
  <p>the server receives the error</p>
  
  <pre><code>error_reason=user_denied
     &amp;error=access_denied
     &amp;error_description=The+user+denied+your+request.
     &amp;state=YOUR_STATE_VALUE
  </code></pre>
  
  <p>What is the reason for this behaviour?</p>