IE Null Error on Google Map API

Hi all
Getting a error message 'markers[…].1 is a null or not an object.
Cant seem to fix it works fine in Firefox etc
Any help would be great

function initializeMaps() {
var myOptions = {

   		mapTypeId: google.maps.MapTypeId.ROADMAP,
		mapTypeControl: false
	var map = new google.maps.Map(document.getElementById("map_canvas"),myOptions);
	var infowindow = new google.maps.InfoWindow();
	var marker, i;
	var bounds = new google.maps.LatLngBounds();

	for (i = 0; i < markers.length; i++) {
		var pos = new google.maps.LatLng(markers[i][1], markers[i][2]);
		marker = new google.maps.Marker({
			position: pos,
			map: map
		google.maps.event.addListener(marker, 'click', (function(marker, i) {
			return function() {
				infowindow.setContent(markers[i][0]);, marker);
		})(marker, i));
	var listener = google.maps.event.addListener(map, "idle", function() {

if (map.getZoom() > 16) map.setZoom(16);

Where is your markers variable been set as I don’t see it anywhere in your above code snippet.