title: MaskedEditValidator causes Page.IsValid to be false when using "en-GB" culture
body: <pre><code>&lt;asp:TextBox id="txtDate" runat="server" Width="70" Text='&lt;%# DataBinder.Eval(Container.DataItem, "Date") %&gt;'/&gt;  
  &lt;atk:MaskedEditExtender ID="meeDate" CultureName="en-GB" runat="server" Mask="99/99/9999" MaskType="Date" TargetControlID="txtDate" PromptCharacter="_" /&gt;          
  &lt;atk:MaskedEditValidator ID="mevDate" runat="server" ControlExtender="meeDate" ControlToValidate="txtDate" EmptyValueMessage=" *" InvalidValueMessage="Date is invalid" IsValidEmpty="False" CssClass="validatorError" /&gt; 
  </code></pre>
  
  <p>The following setup seems to work fine on the client side (the validator validates perfectly against dd/MM/yyyy), however when I post back and check Page.IsValid, the value is false.  I looked at mevDate.IsValid and it's false.  It seems that setting the CultulreName on the MaskedEditExtender is sufficient to get the MaskedEditValidator to emit the correct JavaScript, but on the server side of things it doesn't work.  When I flip CultureName to "en-US" everything works as expected, both on client and server.</p>
  
  <p><strong>UPDATE</strong></p>
  
  <p>One interesting thing I noticed is during debugging if you look at the MaskedEditValidator members, you’ll notice that the <strong>private</strong> member _Culture is set to “en-US” while the MaskedEditExtender is properly set to “en-GB”.  There doesn't seem to be a way to change this.</p>
  
  <p><strong>UPDATE 2</strong></p>
  
  <p>I ended up with the solution I posted below.</p>