I tried to reproduce your issue with our latest official release and it seems that the code works as expected on our side. Can you please take a look at the attached project and see if I missed something. If so I will kindly ask you to change the attached project so we will be able to reproduce your issue on our side and send it over. By doing this we will be able to fully understand your scenario and suggest the best approach in your case.
Thank you for your cooperation.
Pavel R. Pavlov
the Telerik team