title: Drag Drop behavior not working with Prime faces 3.4
body: <p>I recently moved to Prime faces 3.4RC1 from 3.3.1 and noticed that the drag drop behavior stopped working.</p>
  
  <p>I am currently dragging and dropping between 2 different panels. And I have a listener configured to process the drop event :</p>
  
  <pre><code>&lt;p:droppable for="testPanel" scope="all"&gt;
      &lt;p:ajax listener="#{testController.dropUser}" process="@form"  update="@form"/&gt;
  &lt;/p:droppable&gt;
  </code></pre>
  
  <p>The dropUser method is not even invoked after I moved to the latest version. I looked around for any outstanding issue related to the drag drop behaviour and could not find one. Does anyone have any idea what is wrong?</p>