Dynamic Drop down Form Loading

[JZM]

Hey,

Were I am stuck is with the jquery

I have a form that is done in a form class and when an option is selected from the dynamically populated drop down menu I would like it to fill in the text boxes so they can be edited.

I currently have:

getfeed.php - the page that is connected to the javascript

<?php

	include('class/class.form.php');
	
	include('class/class.users.php');

	$iID     = trim($_GET['extension']);
	
	if(!$iID) die('No User Data found.');
	
	$getValues = new Extension();

	$user_info = $getValues->getUsersInformation($iID);

	$sip_info  = $getValues->getSipInformation($iID);
	
	//print_r($user_info);
	
	//print_r($sip_info);
	
	$array = $getValues->getUsersInformation($iID);
		
	
	echo '<br /><br />-- end of query --';

The Javascript

if(document.id('LoadExtension') && document.id('ExtensionResponse')) { // id of select box
	var sel = document.id('LoadExtension'); // ser select box as var.
	sel.addEvent('change', function(chg) { // add change event to select box.
		if(sel.getSelected().get('value') != '') { // on change if selected value is not empty.
			new Request.HTML({
				url : 'http://Domain.co.nz/Air/includes/getFeed.php?extension='+ sel.getSelected().get('value'),
				onRequest: function() {
					document.id('ExtensionResponse').set('html', 'loading...');
				},
				onComplete: function(r1, r2, html, js) {
					document.id('ExtensionResponse').set('html', html);
				}
			}).send();
		}
	});
}

At the moment it does not load any data(I somehow need to get the $iID sent from the index.php but the drop down menu is a count array would I take it from this?) and is in a separate div below the form.