вариант ...
<!DOCTYPE HTML>
<html>
<head>
<meta charset="utf-8" />
<style type="text/css">.d1{height:100px;width:100px;background:#F00;border-radius:50px;border:solid 1px #000}
.d2{height:50px;width:50px;margin:25% auto;background:#000;border-radius:25px;border:solid 1px #000;color:#FFFFFF; text-align: center;}
</style>
<script src="http://code.jquery.com/jquery-latest.js"></script>
<script type="text/javascript">
$(window).load(function(){
$('.d1').click(function(event){
alert(event.target == this ? "Ok" : "No pasaran!")
});
});
</script>
<title></title>
</head>
<body>
<div class="d1">
<div class="d2">d2</div>
</div>
</body>
</html>