diff --git a/calendar/inc/class.calendar_ical.inc.php b/calendar/inc/class.calendar_ical.inc.php
index ee806f5f19..5cf1722ee8 100644
--- a/calendar/inc/class.calendar_ical.inc.php
+++ b/calendar/inc/class.calendar_ical.inc.php
@@ -2707,7 +2707,7 @@ class calendar_ical extends calendar_boupdate
 					break;
 				case 'RRULE':
 					unset($vcardData['recur_type']);	// it wont be set by +=
-					$vcardData += calendar_rrule::parseRrule($attributes['value']);
+					$vcardData += calendar_rrule::parseRrule($attributes['value'], false, $vcardData);
 					if (!empty($vcardData['recur_enddate'])) self::check_fix_endate ($vcardData);
 					break;
 				case 'EXDATE':	// current Horde_Icalendar returns dates, no timestamps
diff --git a/calendar/inc/class.calendar_rrule.inc.php b/calendar/inc/class.calendar_rrule.inc.php
index e8504248a0..d14055a015 100644
--- a/calendar/inc/class.calendar_rrule.inc.php
+++ b/calendar/inc/class.calendar_rrule.inc.php
@@ -982,13 +982,13 @@ class calendar_rrule implements Iterator
 	/**
 	 * Parse an iCal recurrence-rule string
 	 *
-	 * @param type $recurence
+	 * @param string $recurence
 	 * @param bool $support_below_daily =false true: support FREQ=HOURLY|MINUTELY
-	 * @return type
+	 * @param array $vcardData =[] already parsed values, specially value for "start" is used if no explicit BYDAY attribute
+	 * @return array
 	 */
-	public static function parseRrule($recurence, $support_below_daily=false)
+	public static function parseRrule($recurence, $support_below_daily=false, array $vcardData=[])
 	{
-		$vcardData = array();
 		$vcardData['recur_interval'] = 1;
 		$matches = null;
 		$type = preg_match('/FREQ=([^;: ]+)/i',$recurence,$matches) ? $matches[1] : $recurence[0];