diff --git a/calendar/inc/class.calendar_ical.inc.php b/calendar/inc/class.calendar_ical.inc.php
index a413b5119f..8df3e16e5e 100644
--- a/calendar/inc/class.calendar_ical.inc.php
+++ b/calendar/inc/class.calendar_ical.inc.php
@@ -522,6 +522,8 @@ class calendar_ical extends calendar_boupdate
 
 					case 'CLASS':
 						$attributes['CLASS'] = $event['public'] ? 'PUBLIC' : 'PRIVATE';
+						// Apple iCal on OS X uses X-CALENDARSERVER-ACCESS: CONFIDENTIAL on VCALANDAR (not VEVENT!)
+						if (!$event['public']) $vcal->setAttribute('X-CALENDARSERVER-ACCESS', 'CONFIDENTIAL');
 						break;
 
     				case 'ORGANIZER':
@@ -2199,7 +2201,7 @@ class calendar_ical extends calendar_boupdate
 		}
 
 		if (!is_a($component, 'Horde_iCalendar_vevent') ||
-			!($event = $this->vevent2egw($component, $component->getAttribute('VERSION'), $this->supportedFields, $principalURL)))
+			!($event = $this->vevent2egw($component, $component->_container->getAttribute('VERSION'), $this->supportedFields, $principalURL)))
 		{
 			return false;
 		}
@@ -2999,6 +3001,14 @@ class calendar_ical extends calendar_boupdate
 			$event['recur_enddate'] = egw_time::to($last, 'server');
 		}
 
+		// Apple iCal on OS X uses X-CALENDARSERVER-ACCESS: CONFIDENTIAL on VCALANDAR (not VEVENT!)
+		if (($x_calendarserver_access = $component->_container->getAttribute('X-CALENDARSERVER-ACCESS')) &&
+			!is_a($x_calendarserver_access, 'PEAR_Error'))
+		{
+			$event['public'] =  (int)(strtoupper($x_calendarserver_access) == 'PUBLIC');
+		}
+		//error_log(__METHOD__."() X-CALENDARSERVER-ACCESS=".array2string($x_calendarserver_access).' --> public='.array2string($event['public']));
+
 		// if no end is given in iCal we use the default lenght from user prefs
 		// whole day events get one day in calendar_boupdate::save()
 		if (!isset($event['end']))
diff --git a/phpgwapi/inc/class.groupdav.inc.php b/phpgwapi/inc/class.groupdav.inc.php
index 51a5e2ff5a..4ea419b2c7 100644
--- a/phpgwapi/inc/class.groupdav.inc.php
+++ b/phpgwapi/inc/class.groupdav.inc.php
@@ -289,11 +289,14 @@ class groupdav extends HTTP_WebDAV_Server
 	 */
 	function OPTIONS($path, &$dav, &$allow)
 	{
-		if (preg_match('#/(calendar|inbox|outbox)/#', $path))
+		// locking support
+		$dav[] = '2';
+
+		if (preg_match('#/(calendar(-[^/]+)?|inbox|outbox)/#', $path))	// eg. /<username>/calendar-<otheruser>/
 		{
 			$app = 'calendar';
 		}
-		elseif (strpos($path, '/addressbook/') !== false)
+		elseif (preg_match('#/addressbook(-[^/]+)?/#', $path))	// eg. /<username>/addressbook-<otheruser>/
 		{
 			$app = 'addressbook';
 		}
@@ -307,11 +310,12 @@ class groupdav extends HTTP_WebDAV_Server
 			$dav[] = 'calendar-proxy';
 			// required by iOS iCal to use principal-property-search to autocomplete participants (and locations)
 			$dav[] = 'calendarserver-principal-property-search';
+			// required by iOS & OS X iCal to show private checkbox (X-CALENDARSERVER-ACCESS: CONFIDENTIAL on VCALENDAR)
+			$dav[] = 'calendarserver-private-events';
 			// other capabilities calendarserver announces
 			//$dav[] = 'calendar-schedule';
 			//$dav[] = 'calendar-availability';
 			//$dav[] = 'inbox-availability';
-			//$dav[] = 'calendarserver-private-events';
 			//$dav[] = 'calendarserver-private-comments';
 			//$dav[] = 'calendarserver-sharing';
 			//$dav[] = 'calendarserver-sharing-no-scheduling';