I have gone through the above link and tried the demo application implemented by telerik. It is working fine on my end. I guess you have missed out the script file which contains the necessary code snippets.
Since this post is now approximately 6 months old, has this capability been added in a recent version, or should we still attempt to use the linked to workaround?
answered on 24 Feb 2010, 03:11 PM
We will consider support for hierarchy with client load mode and client-side binding for the future major versions of RadGrid for ASP.NET AJAX. Note that this feature will not be available for the Q1 2010 release and you can consider the solution from the blog post posted by my colleague Daniel.
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