diff --git a/addons/google_calendar/google_calendar.py b/addons/google_calendar/google_calendar.py
index 995490c3cca..3a242a7c02a 100644
--- a/addons/google_calendar/google_calendar.py
+++ b/addons/google_calendar/google_calendar.py
@@ -205,8 +205,8 @@ class google_calendar(osv.AbstractModel):
         if not context:
             context = {}
         if event.allday:
-            start_date = fields.datetime.context_timestamp(cr, uid, datetime.strptime(event.start, tools.DEFAULT_SERVER_DATETIME_FORMAT), context=context).isoformat('T').split('T')[0]
-            final_date = fields.datetime.context_timestamp(cr, uid, datetime.strptime(event.stop, tools.DEFAULT_SERVER_DATETIME_FORMAT) + timedelta(days=1), context=context).isoformat('T').split('T')[0]
+            start_date = event.start_date
+            final_date = (datetime.strptime(event.stop_date, tools.DEFAULT_SERVER_DATE_FORMAT) + timedelta(days=1)).strftime(tools.DEFAULT_SERVER_DATE_FORMAT)
             type = 'date'
             vstype = 'dateTime'
         else: