A piece of JavaScript on one of our pages gives an access denied error.
In itself nothing strange, it's a reasonably well defined error after all :)

What is strange is that the error ONLY happens on that page (despite identical calls to the JavaScript function appearing on several other pages) and that the error ONLY appears if the page is loaded in a fresh browser instance. If I reload the page before executing the script (which is triggered in the onblur event of a formfield) the error does not appear and the script is executed successfully.

The function of this script is to download some data from the application server and pipe that data into an HTML element (in this case a td, in other pages it may be a div).

Can anyone shed some light as to where to look for the cause of this?

Here's the relevant JavaScript and HTML (fragments of course):

var myFrames = new Array();
function frameObj(index) {
    this.busy = true;
    this.index = index;
    obj = document.createElement("iframe");
    obj.style.height = "0px";
    obj.style.width = "0px";
    this.frame = document.body.appendChild(obj);
    if (this.frame.contentWindow)
	this.frameDoc = obj.contentWindow.document;
    else if (this.frame.contentDocument)
	this.frameDoc = obj.contentDocument;
	this.frameDoc = null;
function findFrame() {
    for (i = 0; i < myFrames.length; i++) {
	if (!myFrames[i].busy) {
	    myFrames[i].busy = true;
    if (i >= myFrames.length)
	myFrames[i] = new frameObj(i);
    return myFrames[i];
function getHTML2(oElement, form, data) {
	dataElement = oElement;
    if (!(frame = findFrame()))
    if (frame.frameDoc) {
	elms = form.elements;
	doc = frame.frameDoc;
	doc.write("<html><body><form name=\"send\" method=\"post\" action=\"" +
	  form.action + "\">");
	doc.write("<input type=\"hidden\" name=\"iframe\" value=\"" + frame.index + "\">");
	doc.write("<input type=\"hidden\" name=\"data\" value=\"" + data + "\">");
	for (i = 0; i < elms.length; i++) {
	    elm = elms[i];
	    switch (elm.type) {
	      case 'button':
	      case 'file':
	      case 'reset':
	      case 'submit':
	      case 'checkbox':
				if (elm.checked == false)
	      case 'radio':
		if (elm.value == '')
	    doc.write("<input type=\"hidden\" name=\"" + elm.name +
	      "\" value=\"" + elm.value + "\">");
function getHTMLDone2(ind, result) {
	dataElement.innerHTML = result;
    myFrames[ind].busy = false;

Code is part of a JSP, JSP code resolves correctly.

<script language="JavaScript">
function getOnEnter() {
	if (window.event.keyCode == 13 ) {
		window.event.returnValue = false;
		getHTML2(ss, pageform, 'ss');
function aktieOnEnter(arg) {
	if (window.event.keyCode == 13) {
		window.event.returnValue = false;
function faktie(arg) {
	document.pageform.uaktie.value = arg;
<form name="pageform" action="../servlet/<%= ks.getServletName() %>" method="post">
	<input type="hidden" name="pageid" value="<%= request.getAttribute("pageid") %>">
	<input type="hidden" name="uaktie" value="<%= uaktie.getJSPValue() %>">
<div class="inh">
	<table class="inh" border="0" cellpadding="0" cellspacing="0">
			<td rowspan="3"><img src="../lib/login.gif"></td>
			<td class="rowhead">Naam</td>
			<td><input class="text" type="text" name="naam" 
			  value="<%= naam.getJSPValue() %>" 
			   onblur="getHTML2(ss, pageform, 'ss');"

			<td class="rowhead">Wachtwoord</td>
			<td><input class="text" type="password" name="wachtwoord"
			  value="<%= wachtwoord.getJSPValue() %>" /></td>
			<td class="rowhead" id="sh">
			<td id="ss">

OK, let's bump this up and provide a small update :)

It seems the problem happens only on Win XP with SP2 installed, on SP1 machines the code seems to works fine.

Anyone know what changes there are in the Javascript engine of IE6 between SP1 and SP2?

I get the same problem.
Have you figured out what to do?
Please let me know if you have. I belive it has something to do with "document.write"