/**
* Create Xml Http Request object
*/	
function create_http_request()
{
	var xmlhttp = null;
	if (window.XMLHttpRequest) {
	  xmlhttp = new XMLHttpRequest();
	  if (typeof xmlhttp.overrideMimeType != 'undefined') {
	    xmlhttp.overrideMimeType('text/xml');
	  }
	} 
	else if (window.ActiveXObject) {
	  xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
	}
	return xmlhttp;
}