diff --git a/addons/calendar/calendar.py b/addons/calendar/calendar.py
index 45919e6b024..711b37c205a 100644
--- a/addons/calendar/calendar.py
+++ b/addons/calendar/calendar.py
@@ -479,13 +479,13 @@ class calendar_alarm_manager(osv.AbstractModel):
 
     def get_next_notif(self, cr, uid, context=None):
         ajax_check_every_seconds = 300
-        partner = self.pool.get('res.users').browse(cr, uid, uid, context=context).partner_id
+        partner = self.pool['res.users'].read(cr, SUPERUSER_ID, uid, ['calendar_last_notif_ack'], context=context)
         all_notif = []
 
         if not partner:
             return []
 
-        all_events = self.get_next_potential_limit_alarm(cr, uid, ajax_check_every_seconds, partner_id=partner.id, mail=False, context=context)
+        all_events = self.get_next_potential_limit_alarm(cr, uid, ajax_check_every_seconds, partner_id=partner['id'], mail=False, context=context)
 
         for event in all_events:  # .values()
             max_delta = all_events[event]['max_duration']
@@ -495,7 +495,7 @@ class calendar_alarm_manager(osv.AbstractModel):
                 LastFound = False
                 for one_date in self.pool.get("calendar.event").get_recurrent_date_by_event(cr, uid, curEvent, context=context):
                     in_date_format = one_date.replace(tzinfo=None)
-                    LastFound = self.do_check_alarm_for_one_date(cr, uid, in_date_format, curEvent, max_delta, ajax_check_every_seconds, after=partner.calendar_last_notif_ack, mail=False, context=context)
+                    LastFound = self.do_check_alarm_for_one_date(cr, uid, in_date_format, curEvent, max_delta, ajax_check_every_seconds, after=partner['calendar_last_notif_ack'], mail=False, context=context)
                     if LastFound:
                         for alert in LastFound:
                             all_notif.append(self.do_notif_reminder(cr, uid, alert, context=context))
@@ -505,7 +505,7 @@ class calendar_alarm_manager(osv.AbstractModel):
                         break
             else:
                 in_date_format = datetime.strptime(curEvent.start, DEFAULT_SERVER_DATETIME_FORMAT)
-                LastFound = self.do_check_alarm_for_one_date(cr, uid, in_date_format, curEvent, max_delta, ajax_check_every_seconds, after=partner.calendar_last_notif_ack, mail=False, context=context)
+                LastFound = self.do_check_alarm_for_one_date(cr, uid, in_date_format, curEvent, max_delta, ajax_check_every_seconds, after=partner['calendar_last_notif_ack'], mail=False, context=context)
                 if LastFound:
                     for alert in LastFound:
                         all_notif.append(self.do_notif_reminder(cr, uid, alert, context=context))