I created my own skin, and i called the jquery in ascx file like this...

<script type="text/javascript" src="<%# ResolveUrl("~/js/jquery.prettyPhoto.js")%>"></script>

<script type="text/javascript" >
   $(document).ready(function() {
       $("a[rel^='prettyPhoto']").prettyPhoto();
   });
 </script>

And the code in a module is 

<ul id="portfolio-list" class="gallery">
    <li class="cat-images">
    <a href="/trotech_latest/portals/0/Skins/Reasonable/images/dummy-big-image.jpg" rel="prettyPhoto[images]">
    <span></span>
    <img alt="" src="/trotech_latest/portals/0/Images/dummy-gallery-thumb.jpg" /></a>
    <em>Image</em>
    </li>

</ul>

But its not working , Thanks in advance for your help.