title: RequiredFieldValidator with ValidationGroup doesn't validate
body: <p>Here's my markup:</p>
  
  <pre><code>Name: 
  &lt;asp:TextBox ID="txtNewName" runat="server" ValidationGroup="NewDepartmentValidationGroup" /&gt;
  &lt;asp:RequiredFieldValidator ID="vldtxtNewName" runat="server" ControlToValidate="txtNewName"
      ErrorMessage="Required Field" /&gt;&lt;br /&gt;
  Description: 
  &lt;asp:TextBox ID="txtNewDescription" runat="server"          
      ValidationGroup="NewDepartmentValidationGroup"/&gt;
  &lt;asp:RequiredFieldValidator ID="vldtxtNewDescription" runat="server" 
      ControlToValidate="txtNewDescription" ErrorMessage="Required Field" /&gt;&lt;br /&gt;
  &lt;asp:Button ID="cmdCreate" runat="server" Text="Create"
       ValidationGroup="NewDepartmentValidationGroup" OnClick="cmdCreate_Click" /&gt;
  </code></pre>
  
  <p>When I remove ValidationGroup attribute, the behavior is as expected and the client side code warns that the field is required. </p>
  
  <p>But when I specify ValidationGroup (as noted in the example above) and I click the button with the text boxes empty, the client side code does nothing, the button click event fires and the Page.IsValid equals true and my code proceeds, contrary to what is expected. </p>
  
  <p>Any ideas how to fix this?</p>