function expand(dom_id, text_id){
   var url="/richtexts/json/"+text_id
   var d = loadJSONDoc(url);
   var target_dom_node = document.getElementById(dom_id);
   var gotInfos = function(result){
      result.text += "<div style=\"clear:both;\">&nbsp;</div>";
      target_dom_node.innerHTML = result.text
   }

   var fetchFailed = function(err){
      // todo error message
   }
   d.addCallbacks(gotInfos, fetchFailed);
}