茅台帝赐玉酒:JSP还是报"标准表达式中数据类型不匹配"

[Microsoft][ODBC Microsoft Access Driver] 标准表达式中数据类型不匹配。
程序段如下，到底哪有问题？有好几个程序都报这样的错！
<%
String id1 =(String)session.getAttribute("id");
String mysql;
%>
<h1>
学生<%=session.getAttribute("id")%>,你的个人信息:
</h1>
<%
try{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
Connection con = DriverManager.getConnection("jdbc:odbc:jn" );
Statement stmt = con.createStatement();
mysql = "select * from user where id=' "+id1+" ' ";
ResultSet rs = stmt.executeQuery(mysql);

%>
<table border = "1" width = "600">
<tr>
<td><b>学号<b></td>
<td><b>密码<b></td>
<td><b>姓名<b></td>
<td><b>性别<b></td>
<td><b>出生日期<b></td>
<td><b>Email地址<b></td>
</tr>
<%
if (rs != null){
// while (rs.next()){
%>
<tr>
<td><%=rs.getString("id")%></td>
<td><%=rs.getString("pwd")%></td>
<td><%=rs.getString("name")%></td>
<td><%=rs.getString("sex")%></td>
<td><%=rs.getString("born")%></td>
<td><%=rs.getString("email")%></td>
</tr>
<%
//}
}
rs.close();
stmt.close();
con.close();
}catch (Exception ex){
out.println(ex.getMessage());
}