ext this.model.prototype 有关问题 _Ajax

ext this.model.prototype 问题
小弟碰见个弱弱的问题，大家帮帮忙！
JSP代码：
<%@ page contentType="text/html; charset=UTF-8" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>业务曲线</title>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<link rel="stylesheet" type="text/css" href="../../script/ext-4.0.7/resources/css/ext-all.css" />
<script type="text/javascript" src="../../script/ext-4.0.7/ext-all.js"></script>
<script type="text/javascript" src="../../jsp/frame/js/tradeBight.js"></script>
</head>
<body >
<div id="container">

</div>
</body>

</html>
JS代码：
var store1 = new Ext.data.Store({
        proxy: new Ext.data.HttpProxy({
         url: '/ZHPT/main!getTradeBight.action?dateTime='+new Date().getTime()
        }),
        reader: new Ext.data.JsonReader({
            root: 'ZHPT',
            totalProperty: "results",
            fields:["startDate","zje","zbs"]
        }),
        remoteSort: true
    });
    store1.load();
返回的JSON：{results:1,ZHPT:[{"zbs":"13","sbzje":"","pageMessage":"","startDate":"2012-04","pageEnd":"","jydm":"","zje":"623.30","cgzbs":"","sbzbs":"","jyjg":"","cgzje":"","jyrq":"","pageStart":"","endDate":"","ywbh":""}]}

我把JS的其他的代码都注释掉了，就这一段代码就报
：
消息: 'this.model.prototype' 为空或不是对象
行: 15
字符: 287492
代码: 0
URI: http://localhost:8080/ZHPT/script/ext-4.0.7/ext-all.js
头痛的很！！
------解决方案--------------------
楼主, 你现在解决了么? 我也跟你碰到同样的问题