diff --git a/addons/base_calendar/base_calendar.py b/addons/base_calendar/base_calendar.py
index a0d578dffce..a735de4b823 100644
--- a/addons/base_calendar/base_calendar.py
+++ b/addons/base_calendar/base_calendar.py
@@ -1111,8 +1111,7 @@ e.g.: Every other month on the last Sunday of the month for 10 occurrences:\
         'base_calendar_alarm_id': fields.many2one('calendar.alarm', 'Alarm'),
         'recurrent_uid': fields.integer('Recurrent ID'),
         'recurrent_id': fields.datetime('Recurrent ID date'),
-        'vtimezone': fields.related('user_id', 'context_tz', type='char', size=24, \
-                         string='Timezone', store=True),
+        'vtimezone': fields.selection(_tz_get, size=64, string='Timezone'),
         'user_id': fields.many2one('res.users', 'Responsible', states={'done': [('readonly', True)]}),
         'organizer': fields.char("Organizer", size=256, states={'done': [('readonly', True)]}), # Map with Organizer Attribure of VEvent.
         'organizer_id': fields.many2one('res.users', 'Organizer', states={'done': [('readonly', True)]}),