ajax中ValidatorCalloutExtender控件使用出现问题

验证方式如下：
          <asp:Table ID="Table1" runat="server" Height="43px" Width="285px" BorderColor="Black" BorderStyle="Solid" BorderWidth="1px" CellPadding="1"  CellSpacing="1" GridLines="Both">
                <asp:TableRow runat="server">
                    <asp:TableCell runat="server"><asp:TextBox ID="TextBox3" runat="server"></asp:TextBox></asp:TableCell>
                    <asp:TableCell runat="server">bbb</asp:TableCell>
                </asp:TableRow>
                <asp:TableRow runat="server">
                    <asp:TableCell runat="server">aaa</asp:TableCell>
                    <asp:TableCell runat="server">bbb</asp:TableCell>
                </asp:TableRow>
            </asp:Table>
            <br />
            <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ControlToValidate="TextBox3"
                Display="None" ErrorMessage="bbbbbbbbbbb"></asp:RequiredFieldValidator>
            <cc1:ValidatorCalloutExtender ID="ValidatorCalloutExtender1" runat="server" TargetControlID="RequiredFieldValidator1">
            </cc1:ValidatorCalloutExtender>

当验证时弹出的错误信息和文本框不在同一位置了，初步判断好像是和table的设置不兼容，如果我把GridLines="Both"改成其他方式就可以正常显示了，有没有谁碰到这个问题的？怎么解决？