using javascript and using JQZoom

Hi
I am trying to create this effect http://www.mind-projects.it/projects/jqzoom/demos.php#demo1
i have tried to include the javascript files but there is also a function that needs to be added so i have used string builder and ClientScript.RegisterStartupScript(t, "FocusScript", jFunction.ToString());
<script type="text/javascript">

$(function() {
    $(".jqzoom").jqzoom();
});
</script>


but not sure why its not working?
i have included the js files as below and think they are correct
if (!ClientScript.IsClientScriptIncludeRegistered("lightbox"))
            {
                ClientScript.RegisterClientScriptInclude("lightbox& ...