struts2 dhtmlxtree userdata问题

struts2端响应的json数据：有userdata
{"id":"AREA_01","item":[{"checked":null,"child":"1","id":"DEP_01009","im0":null,"im1":null,"im2":null,"item":[],"nocheckbox":null,"open":null,"select":null,"text":"保卫处","userData":"[{name:'url',content:'asdasd'}]","userdata":"[{name:'url',content:'asdasd'}]"}dhtmlxtree：
      tree.enableCheckBoxes(true);
      tree.setDataMode("json");
      tree.setXMLAutoLoading(xmlAutoLoad);
      tree.loadJSON(loadJSON);
在客户端死后得不到userdata的值？？？请问有遇到这样的问题没？