title: Need help avoid HIERARCHY_REQUEST_ERR: DOM Exception 3 error
body: <p>I'm using javascript with backbone and adobe air. In my view model, I have a parse function where it saves the response( Dom object ), later on, when user hits saves, I want to add a couple of nodes to that saved response but I'm getting Dom exception 3, any help? Here are some code for reference.</p>
  
  <pre><code>parse: function(resp, xhr){
         this.treeDoc = xhr.responseXML
         //parse routine
        }
  </code></pre>
  
  <p>Somewhere down the road, when user wants to save</p>
  
  <pre><code>var xmlTree = createMyXML(); //creates a sub xml tree
  this.treeDoc.appendChild(xmlTree ); //DOM Error 3 thrown
  </code></pre>
  
  <p>Any advice?</p>