jQuery bound keyboard press up event

<script type="text/javascript">
    $(document).ready(function(){

        $("#index_registerForm input[name='rePwd']").unbind('keyup');
        $("#index_registerForm input[name='rePwd']").bind('keyup',function(event){

            if(event.keyCode == '13')
                {
                $("#index_registerForm").submit();
                }


        });




    });


</script>