关于cookieparameter获取cookie值的问题，在线等！

Question

我在登录页面产生了如下cookie值:
HttpCookie cookie = Request.Cookies["LjmsCookie"];
if (cookie == null)
{
   cookie = new HttpCookie("LjmsCookie");
   cookie.Values["teacherID"] = intTeacherID.ToString();
   DateTime dt = DateTime.Now;
   TimeSpan ts = new TimeSpan(8, 0, 0);
   cookie.Expires = dt.Add(ts);
   cookie.Path = "/";
   Response.Cookies.Add(cookie);
}现在页面中，用到:
<asp:SqlDataSource ID="SqlDataSource1" runat="server" OldValuesParameterFormatString="original_{0}"
        ConnectionString="<%$ ConnectionStrings:DataConnectionString %>" 
        SelectCommand="SELECT * from teacher where teacherID = @TeacherID order by StudentID desc" 
        <SelectParameters>
            <asp:CookieParameter CookieName="LjmsCookie" Name="teacherID" Type="String"/>            
        </SelectParameters>
</asp:SqlDataSource>sqldatasource中没有获得teacherID。我用代码，可以得到teacherID。请问各位朋友，应该如何修改cookieparameter才可以得到teacherID