libbonoboui gnome-2 BonoboControl trouble on activate signal

[gandalfn <gandalfn club-internet fr>]

hi,

I would like develop a bonobo2 control component who plug in a shell
interface. This component have ui interface who merge with the shell.
After a look in sample and source of libbonoboui I created a callback
for the signal "activate" who load xml bonoboui interface :

  ui_component = bonobo_control_get_ui_component (control);
  if (state) /* Activate */
    bonobo_ui_util_set_ui (ui_component, 
                           PACKAGE_DATA_DIR "/gnome-2.0/ui/" , 
                           GNOME_BAD_DOWNLOAD_UI_XML,
		           "GNOME_bad_download", NULL);
  else /* De-activate */
    bonobo_ui_component_unset_container (ui_component, NULL);

and in component factory I connect callback to BonoboControl signal

  control = bonobo_control_new (widget);
  bonobo_control_set_automerge(control, TRUE);
  g_signal_connect(G_OBJECT(control), "activate",
                   G_CALLBACK (gnome_bad_download_control_on_activate),
 		   NULL);
  ui_component = bonobo_control_get_ui_component (control);
  bonobo_ui_component_add_verb_list_with_data (ui_component, 
                                               ui_verbs, 
                                               control);
	

In start it's work fine but the switch to another window hide the menu
and toolbar in shell window !

Any idea what is wrong?

Thanks a lot