PEtit probleme jquery

<div id="imbox"> <a href="" title=""><img src="" width="67" height="67" /><span><img src="" width="67" height="67" /></span></a> </div>
<div id="imbox"> <a href="" title=""><img src="" width="67" height="67" /><span><img src="" width="67" height="67" /></span></a> </div>

<script type="text/javascript">                       
 
         
 
  
   $(function(){
	$("#imbox a").hover(function(){
		$(this).children("span").fadeOut();
	}, function(){
		$(this).children("span").fadeIn();
	})	
	});
     
  </script>