diff --git a/addons/calendar/calendar.py b/addons/calendar/calendar.py
index 8ccf6639f86..21e530e8020 100644
--- a/addons/calendar/calendar.py
+++ b/addons/calendar/calendar.py
@@ -1654,6 +1654,14 @@ class calendar_event(osv.Model):
         self.create_attendees(cr, uid, [res], context=context)
         return res
 
+    def export_data(self, cr, uid, ids, *args, **kwargs):
+        """ Override to convert virtual ids to ids """
+        real_ids = []
+        for real_id in get_real_ids(ids):
+            if real_id not in real_ids:
+                real_ids.append(real_id)
+        return super(calendar_event, self).export_data(cr, uid, real_ids, *args, **kwargs)
+
     def read_group(self, cr, uid, domain, fields, groupby, offset=0, limit=None, context=None, orderby=False, lazy=True):
         context = dict(context or {})