Hi guys. I wanted to show you a gallery that I am doing. I'm stuck here with some issue. I've made the gallery with the buttons but now I wanted to add a previous and next button but I not being able to do. all the rest is working.

the javascript code is this:
Code:
$(function () {
var imgContainers = $('div.tabs > div');
imgContainers.hide().filter(':first').show();
			
$('div.tabs ul.number_nav a').click(function () {
imgContainers.hide();
imgContainers.filter(this.hash).show();
$('div.tabs ul.number_nav a').removeClass('selected');
$(this).addClass('selected');
return false;
}).filter(':first').click();
});
the html file is this:
Code:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
  "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<title>gallery</title>

<!--CSS-->

<link href="style.css" rel="stylesheet" type="text/css" />

<!--JavaScript-->
<script type="text/javascript" src="jquery-1.4.2.js"></script>

<script type="text/javascript" src="code.js"></script>

</head>
<body>
<div id="gallery"><!--IMG CONTAINER START -->
<div class="tabs">

<div id="image_01">
<div class="image">
<img src="image_one.png" width="795" height="395" />
</div>
</div>

<div id="image_02" >
<div class="image">
<img src="image_two.png" width="795" height="395" />
</div>
</div>

<div id="image_03">
<div class="image">
<img src="and_so_on.png" width="795" height="395" />
</div>
</div>


<ul class="number_nav">
<li><a href="#image_01">01</a></li>
<li><a href="#image_02">02</a></li>
<li><a href="#image_03">03</a></li>
</ul>

<ul class="prev_next_nav">
<li><a href="#">Previous</a></li> 
/ <li><a href="#">Next</a></li>
</ul>
</div>
</div>


</body>

</html>
gallery.zip

can someone help me to make the code to the previous / next buts please? I'm not very good ( nothing at all ) with javascript...

thanks in advance