请大侠帮我看 下这个错误怎么解决？谢谢了！

我做的是个书上的例子，是个意见箱，提交以后到第二个页面可以看到留的意见。下面是我的代码index.jsp
<!--index.jsp-->
<script language=javascript>
//函数isEmpty()用来判断一个输入域是否为空
function isEmpty(str)
{ if((str==null)||(str.length==0)) return true;
else return(false);
}
//函数isEmail()用来判断一个输入域是否为合法的邮件地址
function isEmail(theStr)
{ var atIndex=theStr.indexOf('@");
var dotIndex=theStr.indexOf('.',atIndex);
var flag=true;
theSub=theStr.substring(o,dotIndex+1)
if((atIndex<1)||(atIndex!=theStr.lastIndexOf('@'))||(dotIndex<atIndex+2)||(theStr.length<=theSub.length))
{flag=false;}
else{flag=true;}
return(flag);}
function checkform(Frm)
{ varflag=true;
if(isEmpty(Frm.name.value))
{ alert("请输入您的姓名！");
Frm.name.focus();
flag=false;
}
else if(!isMail(Frm.mail.value))
{alert("您的邮件地址输入有误!");
Frm.mail.focus();
flag=false;
}
else if(isEmpty(Frm.title.value))
{alert("请输入意见主题!");
Frm.title.focus();
flag=false;
}
else if(isEmpty(Frm.content.value))
{alert("请输入您的意见!");
Frm.content.focus();
flag=false;
}
return flag;
}
</script>
<html>
<head>
<title>意见箱</title>
<meta http-equiv="Content-Type" content="text/html;charset=gb2312">
<style type="text/css">
<!--@import "css/jsp.css";-->
</style>
</head>
<body bgcolor="#FFFFFF" topmargin="1">
<%@ page contentType="text/html;charset=gb2312"%>
<div align="center">
<p> </p>
<table width="500" border="0" cellspacing="1">
<tr>
<td>
<div align="center" >
<table width="500" border="0" cellspacing="2" cellpadding="1">
<tr>
<td width="110">
<%@ page import="java.util.*"%>
<div align="center">^o^
<% java.util.Date m_date=new java.util.Date();
int nowHour=m_date.getHours();
if(nowHour<=6)
{%>凌晨<%}
else if(nowHour<=11)
{%>上午<%}
else if(nowHour<=13)
{%>中午<%}
else if(nowHour<=18)
{%>下午<%}
else
{%>晚上<%}%>好</div>
</td>
<td width="232">
<div align="center"><font size="6" face="Fixedsys.黑体,仿宋_GB2312">意见箱
</font>
</div>
</td>
<td width="144">今天是：<%String nowDate=m_date.toLocaleString();
nowDate=nowDate.substring(0,10);
out.print(nowDate);
%></td>
</tr>
</table>
<form name="form" method="post" action="idea.jsp" onsubmit="return checkform(this)">
<div align="center">
<table width="500" cellspacing="1">
<tr>
<td rowspan="2">
<div align="right">您的姓名：</div>
</td>
<td colspan="3" rowspan="2">
<input type="text" name="name" size="13">
</td>
</tr>
<tr></tr>
<tr>
<td width="21%" height="31">
<div align="right">您的EMAIL：</div>
</td>
<td height="31" colspan="3">
<input type="text" name="mail" size="20">
</td>
</tr>
<tr>
<td width="21%">
<div align="right">主题：</div>
</td>
<td colspan="3">
<input type="text" name="title" size="30">
</td>
</tr>
<tr>
<td width="21%">
<div align="right">您的意见：</div>
</td>
<td colspan="3">
<textarea name="content" cols="50" rows="6"></textarea>
</td>
</tr>
<tr>
<td colspan="4">
<div align="center">
<input type="submit" name="Submit" value="提交您的意见">
<input type="reset" name="reset" value="清除重写">
</div>
</td>
</tr>
</table>
</div>
</form>
</div>
</td>
</tr>
</table>
</div>
</body>
</html>