(function(){
    var special = jQuery.event.special,
        uid1 = 'D' + (+new Date()),
        uid2 = 'D' + (+new Date() + 1);       
    special.scrollstart = {
        setup: function() {
            var timer,
                handler =  function(evt) {var _self = this, _args = arguments;
                    if (timer) {clearTimeout(timer);
                    } else {evt.type = 'scrollstart'; jQuery.event.handle.apply(_self, _args);}
                    timer = setTimeout( function(){timer = null;}, special.scrollstop.latency);
                };
            jQuery(this).bind('scroll', handler).data(uid1, handler);
        },
        teardown: function(){jQuery(this).unbind( 'scroll', jQuery(this).data(uid1) );}};
    special.scrollstop = {latency: 300, setup: function() {
            var timer, handler = function(evt) {
                    var _self = this,
                        _args = arguments;
                    if (timer) {clearTimeout(timer);}
                    timer = setTimeout( function(){
                        timer = null;
                        evt.type = 'scrollstop';
                        jQuery.event.handle.apply(_self, _args);
                    }, special.scrollstop.latency);
                };
            jQuery(this).bind('scroll', handler).data(uid2, handler);
        },
        teardown: function() {jQuery(this).unbind( 'scroll', jQuery(this).data(uid2) );}
    };
})();