Make an iFrame object sortable ?

Make an iFrame object sortable ?

Hi, i have an iframe called #iframe and inside that iframe i call a basic html homepage with an ul called #nav with some li's, i wonder if there is a way to make #nav elements sortables without modify the original html loaded through the iframe.

For example i have 2 files ... the one with the iframe (iframe.html) and the one with the homepage (source.html)

In iframe.html i tried this on the head tag:

<script type="text/javascript">
$(document).ready(function(){
      $('#iframe').load(function(){
            $(this).contents().find('#nav').sortable();
      });
});
</script>

And it didn't work, is there a better way to do that (surely) ?

Thanks in advance !