AllowSorting .net

I want to do sorting for which i am setting the following properties but still the headers are not clickable

<asp:datagrid id="DataGrid1" AllowSorting="True" runat="server" CellPadding="4" Font-Size="8" Font-Name="arial" HeaderStyle-BorderColor="#99ff33" ItemStyle-BorderColor="#6cc33" HeaderStyle-BackColor="#ccff66" ItemStyle-BackColor="#ffff00" AutoGenerateColumns="False" PageSize="5" PagerStyle-Position="TopAndBottom" PagerStyle-NextPageText="Next" PagerStyle-PrevPageText="Previous" AllowPaging="true">

Here is a good link on sorting from MSDN
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnaspp/html/aspnet-pageablesortable.asp

See if that helps you out.

Eric