一个效果中遇到的问题

代码如下:
//无法完美显示,主要问题在鼠标放上而又移开后不能紧接着滚动

copycode:

function $(id) {
    return document.getElementById(id);
}
var aa = 0;

var hot_list = {

    x: function(t, t1) {
        var me = this;
        var obj = $(t).getElementsByTagName("ul"),
        len = obj.length;
        var obj1 = obj[1].getElementsByTagName("li"),
        len1 = obj1.length;

        for (var i = 0; i < len1; i++) {

            obj1[i].i = i;
            obj1[i].onmouseover = function() {
                clearInterval(timer);
                hot_list.z(t, this.i);
            }
            obj1[i].onmouseout = function() {
                timer = setInterval(function() {
                    hot_list.p("box");
                },
                1000);
            }

        }

    },
    z: function(t, node) {
        var obj = $(t).getElementsByTagName("ul"),
        len = obj.length;

        var obj1 = obj[0].getElementsByTagName("li"),
        len1 = obj1.length,
        obj2 = obj[1].getElementsByTagName("li");

        for (var j = 0; j < len1; j++) {

            if (obj1[j].className != "none") {
                obj1[j].className = "none";

            }
            if (j == node) {
                obj1[node].className = "act";
            }

            if (obj2[j].className != "none") {
                obj2[j].className = "none";

            }
            if (j == node) {
                obj2[node].className = "act";
            }
        }
    },

    p: function(t, aaa) {
        var me = this;
        var obj = $(t).getElementsByTagName("ul"),
        len = obj.length;
        var obj1 = obj[1].getElementsByTagName("li"),
        len1 = obj1.length;

        if (aa < len1) {

            hot_list.z(t, aa++);

        }
        else {
            aa = 0;
            hot_list.z(t, aa++);
        }
    }
};

hot_list.x("box");
var timer = setInterval(function() {
    hot_list.p("box");
},
1000);

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<style type="text/css">
html { height:100%; width:100%; }
* { padding:0; margin:0; }
body { font-family:Verdana, Geneva, sans-serif; font-size:14px; line-height:22px; }
#wrap { width:700px; margin:0 auto; }
ol, li { list-style:none; }
a { text-decoration:none; color:#000; }
.box ul.img_box { width:300px; float:left; }
.box ul.myul { width:300px; float:right; }
.box ul.img_box li { display:none; }
.box ul.img_box li.none { display:none; }
.box ul.img_box li.act { display:block; }
.box ul.myul a:hover { color:#900; }
.box ul.myul li.none a { color:#000; }
.box ul.myul li.act a { color:#fff; background-color:#090; }
</style>
</head>
<body>
<div id="wrap">
 <div class="box" id="box">
  <ul class="img_box">
   <li class="act"><img src="http://images.movie.xunlei.com/gallery/561/4b9288afce13ad795f5b242121779da4.jpg" alt="" /></li>
   <li>1</li>
   <li>2</li>
   <li>3</li>
   <li>4</li>
   <li>5</li>
   <li>6</li>
   <li>7</li>
   <li>8</li>
  </ul>
  <ul class="myul">
   <li class="act"><span>[新闻]</span><a class="hover" href="#" title="欢迎访问我的小站！">欢迎访问我的小站！</a></li>
   <li><span>[娱乐]</span><a href="#" title="专注前端开发，关注用户体验">专注前端开发，关注用户体验</a></li>
   <li><span>[体育]</span><a href="#" title="一步一步学习js，编辑推荐">一步一步学习js，编辑推荐</a></li>
   <li><span>[图书]</span><a href="#" title="你了解IE6吗？">你了解IE6吗？</a></li>
   <li><span>[汽车]</span><a href="#" title="这是一个神奇的世界">这是一个神奇的世界</a></li>
   <li><span>[房产]</span><a href="#" title="新艺术领域的珠联璧合！">新艺术领域的珠联璧合！</a></li>
   <li><span>[校园]</span><a href="#" title="JavaScript高级程序设计">JavaScript高级程序设计</a></li>
   <li><span>[商城]</span><a href="#" title="ActionScript3殿堂之路">ActionScript3殿堂之路</a></li>
   <li><span>[空间]</span><a href="#" title="你学会了吗？">你学会了吗？</a></li>
  </ul>
 </div>
</div>
<script type="text/javascript">
function $(id) {
    return document.getElementById(id);
}
var aa = 0;

var hot_list = {

x: function(t, t1) {
        var me = this;
        var obj = $(t).getElementsByTagName("ul"),
        len = obj.length;
        var obj1 = obj[1].getElementsByTagName("li"),
        len1 = obj1.length;

for (var i = 0; i < len1; i++) {

obj1[i].i=i;
            obj1[i].onmouseover = function(){
				clearInterval(timer);
                hot_list.z(t, this.i);}
			 obj1[i].onmouseout = function(){
				 timer = setInterval(function() {
    hot_list.p("box");
},
1000);}

}
     
    },
    z: function(t, node) {
        var obj = $(t).getElementsByTagName("ul"),
        len = obj.length;

var obj1 = obj[0].getElementsByTagName("li"),
        len1 = obj1.length,obj2=obj[1].getElementsByTagName("li");
     
        for (var j = 0; j < len1; j++) {

if (obj1[j].className != "none") {
                obj1[j].className = "none";
		
            }
            if (j == node) {
                obj1[node].className = "act";
            }
			  
			  if (obj2[j].className != "none") {
                obj2[j].className = "none";
		
            }
            if (j == node) {
                obj2[node].className = "act";
            }
        }
    },

p: function(t, aaa) {
        var me = this;
        var obj = $(t).getElementsByTagName("ul"),
        len = obj.length;
        var obj1 = obj[1].getElementsByTagName("li"),
        len1 = obj1.length;

if (aa < len1) {

hot_list.z(t, aa++);
			
        }
        else {
            aa = 0;
            hot_list.z(t, aa++);
        }
    }
};

hot_list.x("box");
var timer = setInterval(function() {
    hot_list.p("box");
},
1000);</script>
</body>
</html>

什么问题?
在onmouseout加个aa=this.i就解决了!如下: