why this event repeat

why this event repeat

Hi
The 2nd time I click, the function repeats twice, the 3rd time I click, the function repeats thrice... like a loop depends on my clicks. what is the problem, is it a bug of jquery or a bug of mine. Thanks in advance.

Cheers

<!--============-->
<head>
<script src="jQuery.js" type="text/javascript"></script>
<script>
var i=1;
$(document).ready(function()
{
    $('li').click(function()
    {   
        alert('this:'+i);
        $('li').click(function(){
            i++;
            alert(i);
        })
    })
})
</script>
</head>
<body>
<li>test</li>
</body>
</html>