[nerbert]

Maybe you don't want IE8 types on your forum??????

Well I thought the whole point of all that YAHOO code was browser compatibility. So here's doing it the old fashioned way:

$customfields_profile .= "
	<script>
		fetch_object('cfield_5').parentNode.parentNode.style.display = 'none';
		fetch_object('cfield_5').value = 'NOT APPLICABLE';
                if(document.addEventListener)  document.addEventListener('click', openFields, true);
                else if(document.attachEvent)  document.attachEvent('onclick', openFields);

		function openFields(e) {
			var radio =  e.srcElement || e.target ;
			if(radio.id == 'rb_cpf_field6_1') {
				fetch_object('cfield_5').parentNode.parentNode.style.display = 'block';
				fetch_object('cfield_5').value = '';
			}
			if(radio.id == 'rb_cpf_field6_2') {
				fetch_object('cfield_5').parentNode.parentNode.style.display = 'none';
				fetch_object('cfield_5').value = 'NOT APPLICABLE';
			}
		}
	</script>
";

--------------- Added [DATE]1410966671[/DATE] at [TIME]1410966671[/TIME] ---------------

There's one thing you may wish to consider before changing the code. I think by default vBulletin gets its YUI (Yahoo! User Interface Library) remotely from Google or Yahoo servers. You can change that to local hosting in

Server Settings and Optimization Options > Use Remote YUI = "None"

Getting it remotely is supposed to save bandwidth but I've had trouble with connection failures before.

But the point here is that apparently remotely hosted YAHOO no longer supports IE8 (I think I heard jQuery quit too) but I'm sure your locally hosted vB version still does.