thanks for the good screencast. It pin-pointed very well what I had overlooked.
I had missed the EnableScriptGlobalization property of the radscriptmanager.
<telerik:RadScriptManager runat="server" EnableScriptGlobalization="true">
Setting that did solve my problem. Simple as that :) Sloppy as that on my part :(
The confusing part is they the drop down calendar does follow the locale without setting the property .
Thanks a lot.