JavaScript on XP/IE6 machine

[johannesburgboy]

i am very frustrated with a problem on a clients comps that run XP OS on it. for some strange reason does SOME of the javascript not run on their machines. why is that? i have tried everything. first it gave a runtime error and now they cannot use my scripted buttons? what is going on. is there some sort of setting in IE6 and/or XP that disables 'some' JavaScript?
any help will be appreciated

[AdamBrill]

I am running IE6 with XP and everything seems to be fine. What script where you having a problem with?

[johannesburgboy]

Well, my personal computer (running XP and IE6 along with all computers in the Johannesburg Office has no probs but 2 computers in Chicago cannot use the menu buttons in the left frame. Please have a look.

menu buttons on site:

<script language="JavaScript">
<!--
//By George Chiang (www.javascriptkit.com) JavaScript site.
ns6_index=0

function change(e)
{
if(!document.all&&!document.getElementById)
return

if (!document.all&&document.getElementById)
ns6_index=1

var source=document.getElementById&&!document.all? e.target:event.srcElement

// About
if (source.className=="about"){
var source2=document.getElementById&&!document.all? source.parentNode.childNodes:source.parentElement.all

if (source2[2+ns6_index].style.display=="none"){
source2[0].src="images/aboutn.gif"
source2[2+ns6_index].style.display=''
} else {
source2[0].src="images/aboutn.gif"
source2[2+ns6_index].style.display="none"
}
//(etc..etc)
document.onclick=change
//-->
</script>

Left frame named menu.asp
Click next to image (between mainframe and left frame to view source)

This is all quite strange as all other computers that run this script can view it. :confused: