HI,
Try this code..

echo "<?xml version='1.0' encoding='iso-8859-1'?>
<response>
<imgpath>$path</imgpath>
<imgprice>$price</imgprice>
</response>";
--------------------------

var xml = xmlHttp.responseXML;
var root = xml.documentElement;
path = root.getElementsByTagName("imgpath")[0];
price = root.getElementsByTagName("imgprice")[0];
Thanks,
Ramkumar.B