OK, so the app I'm working on has a page named EditItemView with a RadDatePicker control for entering a Due date. You can get to this page two different ways. The first, which doesn't get the exception is though an 'Add' button on the ApplicationBar and call to a ViewModel that navigates to the EditItemView. The second, which gets the NullReference exception is after holding and item on a list (using GestureListeners from the WP7 toolkit). The hold getsture procs and another method on a ViewModel is called to, again, navigate to the EditViewModel with the RadDatePicker.
In the second situation, when you click the box and bring up the date selector page if you hit any of three boxes to change the date you get an exception. Included is the trace to the exception. I can clarify or provide more information if needed. Anyone had any issues so far with GestureListeners and the RadDatePicker?
at Telerik.Windows.Controls.TiltInteractionInfo.Clear(Boolean animate)
at Telerik.Windows.Controls.TiltInteractionEffect.EndTilting(Boolean animate)
at Telerik.Windows.Controls.TiltInteractionEffect.OnElementManipulationCompleted(Object sender, RoutedEventArgs e)
at MS.Internal.CoreInvokeHandler.InvokeEventHandler(Int32 typeIndex, Delegate handlerDelegate, Object sender, Object args)
at MS.Internal.JoltHelper.FireEvent(IntPtr unmanagedObj, IntPtr unmanagedObjArgs, Int32 argsTypeIndex, Int32 actualArgsTypeIndex, String eventName)