E4X Parsing with HTTP Request Response XML

I put together a simple XML schema for a directory (address-book) markup system. The basic structure is as follows:

<?xml version="1.0" encoding="UTF-8">
<di开发者_JS百科rectory
    xmlns="http://example.com"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://example.com directory.xsd">
    <title>An Example Directory Document</title>
    <creator>Lorem Ipsum Dolor</creator>
    <date>September 29, 2011</date>
    <person>
        <firstName>Lorem</firstName>
        <middleName>Ipsum</middleName>
        <lastName>Dolor</lastName>
        <email type="personal">lorem@ipsum.org</email>
        <email type="other">ispum@dolor.org</email>
        <phone type="mobile">(123) 456-7890</phone>
    </person>
</directory>

This is the JavaScript (and E4X; this is actually only being used if a PHP $_GET[] or $_REQUEST[] variable is true, due to the fact that only Firefox has decent E4X support):

<script type="text/javascript;e4x=1">
var directory;

xmlhttp = new XMLHttpRequest();     
xmlhttp.open('GET', 'http://example.com/directoryExample.xml', true);
xmlhttp.onreadystatechange = (function() {
    if(xmlhttp.readyState === 4) {
        if(xmlhttp.status === 200) {
            directory = xmlhttp.responseXML;
            HandleDirectoryData();
        }
    }
});

function HandleDirectoryData() {
    var container = document.getElementById('output');
    var directoryTitle = directory.title;
    var directoryCreator = directory.creator;
    var directoryDate = directory.date;
    var title = document.createElement('p');
    var creator = document.createElement('p');
    var titleLabel = document.createElement('label');
    var creatorLabel = document.createElement('label');
    title.id = "xmlDirectoryTitle";
    creator.id = "creator";
    titleLabel.for = title.id;
    creatorLabel.for = creator.id;
    titleLabel.textContent = "Title:";
    creatorLabel.textContent = "Creator:";
    titleLabel.appendChild(title);
    creatorLabel.appendChild(creator);
    container.appendChild(titleLabel);
    container.appendChild(creatorLabel);
    for each(var person in XMLData) {
        console.log("Displaying of the person data happens here...");
    }
}

I believe the XMLHttpRequest is fine, and that it is simply the parsing that has something wrong with it.

Thanks in advance!