Problem selecting HTML elements with xpath in Internet Explorer

xpathobj = document.evaluate(xpath, document, null, XPathResult.FIRST_ORDERED_NODE_TYPE, null);

xmlDoc=new ActiveXObject("Microsoft.XMLDOM");
xmlDoc.async=false;
xmlDoc.load(document);
xmlDoc.setProperty("SelectionLanguage", "XPath");
xpathobj = xmlDoc.selectNodes(xpath);

//Specific to project, here i know that the body element will always have the id "top"
//but otherwise the element that is passed in should be first element in the xpath
//statement eg. /HTML/BODY/DIV the element passed in should be HTML
if(!element){
	element = $("top");
	var xpathArrayIndex = 3;
} else {
	var xpathArrayIndex = 1;
}
//split the xpath statement up
var xpathArray = xpath.split("/");

var carryOn = true;
while(carryOn){
	decendents = element.childElements();
	//check to see if we are at the end of the xpath statement
	if(xpathArrayIndex == xpathArray.length){
		return element;
	}
	//if there is only one decendent make it the next element
	if(decendents.size() == 1) {
		element = decendents.first();
	} else {
	//otherwise search the decendents for the next element
		element = getXPathElementByIndex(decendents, xpathArray[xpathArrayIndex]);
	}
	xpathArrayIndex++;
}

var decendentsArray = decendents.toArray();
//seperate the index from the element name
var temp = xpathSegment.split("[");
var elementName = temp[0];
//get the index as a number eg. "9]" to 9
var elementIndex = +temp[1].replace("]", "");
//the number of matching elements
var count = 0;

//keeps track of the number of iterations
var i = 0;
while(count != elementIndex) {
	//if the decendent's name matches the xpath element name increment the count
	if(decendentsArray[i].nodeName == elementName){
		count++;
	}
	i++;
}
var element = decendentsArray[i - 1];
return element;

function getXPathElement(xpath, element){
if(!element){
    element = document;
}
var xpathArray = xpath.split("/");

element = findXPathRoot(xpathArray[0],xpathArray[1],element);

for(var i=1; i<xpathArray.length; i++){
    if(xpathArray[i].toLowerCase()=="html"){
        continue;
    }
    if(!element){
        return element;
    }
    element = getXPathElementByIndex(element.childNodes,xpathArray[i]);
}
return element;
}


function findXPathRoot(rootPath,htmlPath,element){
if(rootPath == ""&&htmlPath.toLowerCase() == "html"){
    return element.documentElement;
}
return document.getElementsByTagName(rootPath)[0];
}
function getXPathElementByIndex(decendents, xpathSegment){
//seperate the index from the element name
var temp = xpathSegment.split("[");
var elementName = temp[0];
//get the index as a number eg. "9]" to 9
if(temp[1]){
    var elementIndex = temp[1].replace("]", "");
}else{
    var elementIndex = 1;
}
//the number of matching elements
var count = 0;
for(var i=0;i < decendents.length; i++){
    if (decendents[i].nodeName.toLowerCase() == elementName.toLowerCase()) {
        count++;
        if(count==elementIndex){
            return decendents[i];
        }
    }
}
return null;
}

xmlDoc.load(document);

xmlDoc.loadXML(document.body.outerHTML)