Обработка нажатия Checkbox

<script src="jquery-1.3.2.js" type="text/javascript" charset="utf-8"></script>
<script src="iphone-style-checkboxes.js" type="text/javascript" charset="utf-8"></script>
 <link rel="stylesheet" href="style.css" type="text/css" media="screen" charset="utf-8" />

<script type="text/javascript" charset="utf-8">
            $(document).ready(function() {
            $(':checkbox').iphoneStyle();
           });
</script>

<h2 id="iphone">Включено по умолчанию</h2>
<input type="checkbox"  checked="checked"/>

<input type="checkbox"id="ch" />
<div id="out"></div>

document.getElementById('ch').addEventListener('change', function(event) {
    var txt = event.target.checked ? 'On' : 'Off';
    document.getElementById('out').innerHTML = txt;
});

$('#ch').change(function(e) {
    var txt = e.target.checked ? 'On': 'Off';
    $('#out').html(txt);
});