// parse the config
var xmlDoc;
if (window.DOMParser)
{
  var parser=new DOMParser();
  xmlDoc=parser.parseFromString(itemPageConfigXml,"text/xml");
}
else // Internet Explorer
{
  xmlDoc=new ActiveXObject("Microsoft.XMLDOM");
  xmlDoc.async="false";
  xmlDoc.loadXML(itemPageConfigXml); 
} 
var headObjElement = xmlDoc.getElementsByTagName('headObj')[0];	
var headObjPrice = parseFloat(headObjElement.getAttribute("price"));
var upsales = headObjElement.getElementsByTagName('upsale');