I have an accordion control which is databound, within each pane I add a datagrid with an image button column, clicking on one of the buttons should cause a popup (modal panel popup extender) which it does.

However it also causes a javascript error

Microsoft JScript runtime error: Sys.InvalidOperationException: Two components with the same id can't be added to the application.
This error was origionally on the popup extender control so a quick google I found this http://forums.asp.net/t/1331672.aspx and applied the fix, however I still get the error but not its on 'ModalPanel$DropShadowBehavior'

Im not sure where to go from here?