help me in using ajax controls in C#.net
i am using them but finally they are not getting displayed.
the watermarker is not being displayed as the default text moreover the box is empty...
here is the code
<asp:ScriptManager ID="ScriptManager1" runat="server" />
<br />
<br />
<br />
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
<asp:TextBoxWatermarkExtender ID="TextBoxWatermarkExtender1" runat="server"
TargetControlID="TextBox1" WatermarkText="helloworld">
</asp:TextBoxWatermarkExtender>
help me please
thanks in advance.