Grab a copy of defunkt's facebox and make sure you include it in your app. Comet won't work without it!
Make sure you have this in your <head>:
<link rel="stylesheet" href="facebox/facebox.css" type="text/css" />
<script src="facebox/facebox.js"></script>
<script src="comet.js"></script>
<!-- This part's optional -->
<script type="text/javascript">
<!--
$(document).keypress(function(e){
if (!e)
e = window.event;
var code = e.keyCode || e.charCode || e.which || 0;
var character = String.fromCharCode(code);
if(character == 'p') {
jQuery.displayProfile();
}
});
// -->
</script>
This just assigns the profiler overlay to a hotkey, in this case p is assigned to open the profiler. If you don't want to include it, then you can always open up Firebug and call jQuery.displayProfile(); via the console.
Facebox is ©defunkt & jQueryProfiler is ©jeresig Comet brought to you in part by me