Exception in Gtk# callback delegate
  Note: Applications can use GLib.ExceptionManager.UnhandledException to handle the exception.
GLib.MissingIntPtrCtorException: GLib.Object subclass FSpot.PhotoPopup must provide a protected or public IntPtr ctor to support wrapping of native object handles.
  at GLib.ObjectManager.CreateObject (IntPtr raw) [0x00000] 
  at GLib.Object.GetObject (IntPtr o, Boolean owned_ref) [0x00000] 
  at GLib.Object.GetObject (IntPtr o) [0x00000] 
  at Gtk.Widget.parentset_cb (IntPtr widget, IntPtr previous_parent) [0x00000] 
   at GLib.ExceptionManager.RaiseUnhandledException(System.Exception e, Boolean is_terminal)
   at Gtk.Widget.parentset_cb(IntPtr widget, IntPtr previous_parent)
   at Gtk.Widget.parentset_cb(IntPtr , IntPtr )
   at GLib.ToggleRef.g_object_remove_toggle_ref(IntPtr , GLib.ToggleNotifyHandler , IntPtr )
   at GLib.ToggleRef.g_object_remove_toggle_ref(IntPtr , GLib.ToggleNotifyHandler , IntPtr )
   at GLib.ToggleRef.Free()
   at GLib.Object.Dispose()
   at Gtk.Object.Dispose()
   at GLib.Object.PerformQueuedUnrefs()
   at GLib.Timeout+TimeoutProxy.Handler()
   at GLib.Timeout+TimeoutProxy.Handler()
   at Gtk.Application.gtk_main()
   at Gtk.Application.gtk_main()
   at Gtk.Application.Run()
   at Gnome.Program.Run()
   at FSpot.Driver.Main(System.String[] args)