diff --git a/calendar/inc/class.calendar_bo.inc.php b/calendar/inc/class.calendar_bo.inc.php
index 1d74373c3f..0c2feeb49a 100644
--- a/calendar/inc/class.calendar_bo.inc.php
+++ b/calendar/inc/class.calendar_bo.inc.php
@@ -895,11 +895,13 @@ class calendar_bo
 			}
 			if (!isset($event['start']) || !isset($event['end']))
 			{
-				$event['start'] = $event_read['start'];
-				$event['end'] = $event_read['end'];
+				$event['start'] = $this->date2usertime($event_read['start']);
+				$event['end'] = $this->date2usertime($event_read['end']);
 			}
 		}
 		if (!$start) $start = $event['start'];
+		$start_obj = new Api\DateTime($start);
+		$read_start = new Api\DateTime($event_read['start']);
 
 		$events = array();
 		$this->insert_all_recurrences($event,$start,$this->date2usertime($this->config['horizont']),$events);