[DotNetDevelopment] order by not working

[BlueVista]

The sort on the childgrid is not working; nothing happens when I click
on the each column header for sort. (I followed Satay's sample:
http://www.codeproject.com/KB/aspnet/EditNestedGridView.aspx) and i am
using object for datasource. please suggest. I uploaded source code
(default.aspx, default.aspx.cs and js file) here.
http://www.superboxhost.com/genericfiles/post.txt