While trying the trick I noticed that I cannot create any calendar items?!?  Actually, the first one I tried to create did not worked out and while trying to save/ignore/cancel evolution finally crashed... At restart the calendar item was there and could be edited (although the trick to get recursive items never worked...).  I've retried to create other calendar entries on my exchange account but it cannot save anything and evolution complains:

evolution:7533): calendar-gui-WARNING **: send_timezone: Failed to add timezone: Impossible d'ajouter le fuseau horaire du calendrier : Cannot push timezone to cache

(evolution:7533): calendar-gui-WARNING **: send_timezone: Failed to add timezone: Impossible d'ajouter le fuseau horaire du calendrier : Cannot push timezone to cache

(evolution:7533): calendar-gui-WARNING **: send_timezone: Failed to add timezone: Impossible d'ajouter le fuseau horaire du calendrier : Cannot push timezone to cache

(evolution:7533): libecal-CRITICAL **: e_cal_client_create_object_sync: assertion `client != NULL' failed

(evolution:7533): libecal-CRITICAL **: e_cal_client_create_object_sync: assertion `client != NULL' failed

(evolution:7533): calendar-gui-WARNING **: send_timezone: Failed to add timezone: Impossible d'ajouter le fuseau horaire du calendrier : Cannot push timezone to cache

(evolution:7533): calendar-gui-WARNING **: send_timezone: Failed to add timezone: Impossible d'ajouter le fuseau horaire du calendrier : Cannot push timezone to cache

(evolution:7533): e-attachment-view.c-CRITICAL **: e_attachment_view_get_store: assertion `E_IS_ATTACHMENT_VIEW (view)' failed
                                                                                                                                                                                                          
(evolution:7533): libecal-CRITICAL **: e_cal_client_get_local_attachment_store: assertion `client != NULL' failed                                                                                         
                                                                                                                                                                                                          
(evolution:7533): libecal-CRITICAL **: e_cal_component_get_uid: assertion `comp != NULL' failed                                                                                                           
                                                                                                                                                                                                          
(evolution:7533): e-attachment-store.c-CRITICAL **: e_attachment_store_save_async: assertion `E_IS_ATTACHMENT_STORE (store)' failed                                                                       
                                                                                                                                                                                                          
(evolution:7533): GLib-GObject-WARNING **: invalid (NULL) pointer instance                                                                                                                                
                                                                                                                                                                                                          
(evolution:7533): GLib-GObject-CRITICAL **: g_signal_handlers_disconnect_matched: assertion `G_TYPE_CHECK_INSTANCE (instance)' failed                                                                     

(evolution:7533): GLib-GObject-WARNING **: invalid (NULL) pointer instance

(evolution:7533): GLib-GObject-CRITICAL **: g_signal_handlers_disconnect_matched: assertion `G_TYPE_CHECK_INSTANCE (instance)' failed


Perhaps this is totally irrelevant to this bug and a new bug should be opened-up, duno?