values do not show in modal extender if button in update Panel??

hi,
I have a form with dropdown list and textbox
there is also an images button that when clicked loads Modal pop up extender from code behind.
in the extender I show the DropDownSelected Value and Value from the Textbox in a LABEL

Without the button in an Ajax Update Panel - it works and the values show in the label

If I wrap the button in Update Panel - the modal extender loads but the values from DDL and Textbox do not show??




ASPX
  <asp:UpdatePanel ID="UpdatePanelTest11" runat="server" >             <ContentTemplate>          <asp:ImageButton ID="ImageButton3" runat="server" CausesValidation="False" ImageUrl="Images/TestNumber.png" onclick="ImageButton1_Click"/ ...