[jQuery] Retrieving values from elements of the same class

[Thierry]

For the following code:

<script src="jquery-1.3.2.js" type="text/javascript"></script>
<script type"text/javascript">
$(document).ready(function()
{
   $('.approve').click(function() {
      alert($('.approve').prev().val());
   });
});

</script>

<div>
   <input type="hidden" value="1" />
   <input type="button" class="approve" value="Approve" />
</div>
<div>
   <input type="hidden" value="2" />
   <input type="button" class="approve" value="Approve" />
</div>
<div>
   <input type="hidden" value="3" />
   <input type="button" class="approve" value="Approve" />
</div>

Each time I click on any of the button, it's returning me 1.  What
should I change in my javascript code to get the proper values 1, 2 or
3?