diff --git a/addons/base_calendar/base_calendar.py b/addons/base_calendar/base_calendar.py
index 27b68003aa2..45a5c8d9f62 100644
--- a/addons/base_calendar/base_calendar.py
+++ b/addons/base_calendar/base_calendar.py
@@ -1559,12 +1559,12 @@ true, it will allow you to hide the event alarm information without removing it.
                 continue
             event_id, date_new = event_id.split('-')
             event_id = [int(event_id)]
-            for record in self.read(cr, uid, event_id, ['date', 'rrule', 'exdate']):
+            for record in self.read(cr, uid, event_id, ['date', 'rrule', 'exdate'], context=context):
                 if record['rrule']:
                     # Remove one of the recurrent event
                     date_new = time.strftime("%Y-%m-%d %H:%M:%S", \
                                  time.strptime(date_new, "%Y%m%d%H%M%S"))
-                    exdate = (record['exdate'] and (record['exdate'] + ',') or '') + ''.join((re.compile('\d')).findall(date_new)) + 'Z'
+                    exdate = (record['exdate'] and (record['exdate'] + ',') or '') + ''.join((re.compile('\d')).findall(date_new))
                     res = self.write(cr, uid, event_id, {'exdate': exdate})
                 else:
                     res = super(calendar_event, self).unlink(cr, uid, event_id)
diff --git a/addons/caldav/calendar.py b/addons/caldav/calendar.py
index c60bccad036..6937248e828 100644
--- a/addons/caldav/calendar.py
+++ b/addons/caldav/calendar.py
@@ -276,6 +276,7 @@ class CalDAV(object):
         timezones = []
         for data in datas:
             tzval = None
+            exfield = None
             vevent = ical.add(name)
             for field in self.__attribute__.keys():
                 map_field = self.ical_get(field, 'field')
@@ -316,6 +317,8 @@ class CalDAV(object):
                             ical = tz_obj.export_cal(cr, uid, None, \
                                          data[map_field], ical, context=context)
                             timezones.append(data[map_field])
+                        if exfield:
+                            exfield.params['TZID'] = [tzval.title()]
                     elif field == 'organizer' and data[map_field]:
                         event_org = vevent.add('organizer')
                         organizer_id = data[map_field][0]
@@ -326,7 +329,10 @@ class CalDAV(object):
                     elif data[map_field]:
                         if map_type in ("char", "text"):
                             if field in ('exdate'):
-                                vevent.add(field).value = map(parser.parse, (data[map_field]).split(','))
+                                exfield = vevent.add(field)
+                                if tzval:
+                                    exfield.params['TZID'] = [tzval.title()]
+                                exfield.value = map(parser.parse, (data[map_field]).split(','))
                             else:
                                 vevent.add(field).value = tools.ustr(data[map_field])
                         elif map_type in ('datetime', 'date') and data[map_field]: