IE7 fejl: documentElement

fileXML = "http://www.flush-it.dk/xml/getXMLData.php";

GDownloadUrl(fileXML, function(data) {
alert(data);
var xml = GXml.parse(data);

var markers = xml.documentElement.getElementsByTagName("marker");

Det er den kode der henter xml'en..

Kode 

     GDownloadUrl("/data5.xml", function(data, responseCode) {
          var xml = GXml.parse(data);

          pausecomp(2000);
    
          var root = xml.documentElement;
          window.alert(root.getElementsByTagName("marker").length)

          });

          function pausecomp(millis)
          {
          var date = new Date();
          var curDate = null;
          
          do { curDate = new Date(); }
          while(curDate-date < millis);
          }