Why isn't this AJAX working for Internet Explorer?

<script language="javascript">

var XMLHttpRequestObject= false;

if (window.XMLHttpRequest) {XMLHttpRequestObject = new XMLHttpRequest();

} else if (window.ActiveXObject) {XMLHttpRequestObject = new ActiveXObject("Microsoft.XMLHTTP");

}

else if (window.ActiveXObject) {XMLHttpRequestObject = new ActiveXObject("Msxml2.XMLHTTP");}

function getData()

{

var lenderNumber=document.getElementById('lenderNumber').value;

var dataSource="reposearch.php?lender_number=" + lenderNumber;

if(XMLHttpRequestObject) {

var obj = document.getElementById('test');

XMLHttpRequestObject.open("GET", dataSource);

XMLHttpRequestObject.onreadystatechange = function()

{

if (XMLHttpRequestObject.readyState == 4 && XMLHttpRequestObject.status == 200) {

obj.innerHTML = XMLHttpRequestObject.responseText;

}

}

XMLHttpRequestObject.send(null);

}

}

function getTable()

{

document.getElementById('table').innerHTML= "<tr><td align='center'><img src='images/loading.gif' /><br />Loading...</td></tr>";

var days_new = <?php echo $days_new; ?>;

var show_only = document.getElementById('show_only').value;

var order = document.getElementById('order').value;

var field = document.getElementById('fieldSelect').value;

var tableSource="ajaxreporttable.php?field=" + field + "&order=" + order + "&show_only=" + show_only + "&days_new=" + days_new;

if(XMLHttpRequestObject){

var table = document.getElementById('table');

XMLHttpRequestObject.open("GET", tableSource);

XMLHttpRequestObject.onreadystatechange = function()

{

if (XMLHttpRequestObject.readyState == 4 && XMLHttpRequestObject.status == 200) {

table.innerHTML = XMLHttpRequestObject.responseText;

}

}

XMLHttpRequestObject.send(null);

}

}

</script>

It works in other browsers, but not Internet Explorer....please help!