Is simple,
in the code behind put this code:
Protected Sub gvReport_PreRender(sender As Object, e As System.EventArgs) Handles gvReport.PreRender
If gvReport.Rows.Count > 0 Then
gvReport.UseAccessibleHeader = True
gvReport.HeaderRow.TableSection = TableRowSection.TableHeader
End If
End Sub
And before, in the client side code put this:
$(document).ready(function(){
$('.dataTable').dataTable({
"bJQueryUI": true,
"sPaginationType": "full_numbers",
"iDisplayLength": 25,
"aLengthMenu": [[25, 50, 100, -1], [25, 50, 100, "Todo"]]
});
});