User Control Button Event Not Triggered On AJAX WebPage

Hi : I have struck with Usercontrol problem . Ex: I have writtern  button click event on Usercontrol.it works fine while placing on  AJAXpage .But if i place the user control with in table  on page.The Button Click event is not triggered. Here  with i have mentioned the Code below.Plz send me suggestion to solve this issue, its very urgent.

My User Control Table:

<%@ Control Language="C#" AutoEventWireup="true" CodeFile="test.ascx.cs" Inherits="usercontrol_test" %>
<table>
    <tr>
        <td width="8px" style="height: 19px">
            <asp:LinkButton ID="lnkPrev" runat="server" OnClick="lnkPrev_Click">lnkPrev</asp:LinkButton></td>
        <td style= ...