diff --git a/calendar/inc/class.calendar_bo.inc.php b/calendar/inc/class.calendar_bo.inc.php
index 33425e4c5c..66b6077a93 100644
--- a/calendar/inc/class.calendar_bo.inc.php
+++ b/calendar/inc/class.calendar_bo.inc.php
@@ -263,7 +263,7 @@ class calendar_bo
 		{
 			$email = $id;
 			$name = '';
-			if (preg_match('/^(.*) *<([a-z0-9_.@-]{8,})>$/i',$email,$matches))
+			if (preg_match('/^(.*) *<([a-z0-9_.@-]{8,})>$/iU',$email,$matches))
 			{
 				$name = $matches[1];
 				$email = $matches[2];
@@ -1477,7 +1477,7 @@ class calendar_bo
 				$id2email[$id] = $GLOBALS['egw']->accounts->id2name($id,'account_email');
 			}
 		}
-		return $id2lid[$id].($append_email && $id2email[$id] ? ' <'.$id2email[$id].'>' : '');
+		return $id2lid[$id].(($append_email || $id[0] == 'e') && $id2email[$id] ? ' <'.$id2email[$id].'>' : '');
 	}
 
 	/**
diff --git a/calendar/inc/class.calendar_ical.inc.php b/calendar/inc/class.calendar_ical.inc.php
index 8dab5f58c7..4e1647fe75 100644
--- a/calendar/inc/class.calendar_ical.inc.php
+++ b/calendar/inc/class.calendar_ical.inc.php
@@ -530,7 +530,7 @@ class calendar_ical extends calendar_boupdate
 						break;
 
     				case 'ORGANIZER':
-	    				if (!$organizerCN)
+	    				if (!$organizerURL)
 	    				{
 	    					$organizerCN = '"' . trim($GLOBALS['egw']->accounts->id2name($event['owner'],'account_firstname')
 			    				. ' ' . $GLOBALS['egw']->accounts->id2name($event['owner'],'account_lastname')) . '"';
@@ -2675,8 +2675,15 @@ class calendar_ical extends calendar_boupdate
 					{
 						$role = $attributes['params']['ROLE'];
 					}
-					// parse email and cn from attendee
-					if (preg_match('/MAILTO:([@.a-z0-9_-]+)|MAILTO:"?([.a-z0-9_ -]*)"?[ ]*<([@.a-z0-9_-]*)>/i',
+					// CN explicit given --> use it
+					if (strtoupper(substr($attributes['value'], 0, 7)) == 'MAILTO:' &&
+						!empty($attributes['params']['CN']))
+					{
+						$email = substr($attributes['value'], 7);
+						$cn = $attributes['params']['CN'];
+					}
+					// try parsing email and cn from attendee
+					elseif (preg_match('/MAILTO:([@.a-z0-9_-]+)|MAILTO:"?([.a-z0-9_ -]*)"?[ ]*<([@.a-z0-9_-]*)>/i',
 						$attributes['value'],$matches))
 					{
 						$email = $matches[1] ? $matches[1] : $matches[3];
@@ -2715,7 +2722,7 @@ class calendar_ical extends calendar_boupdate
 							$uid = $this->user;
 					}
 					// check principal url from CalDAV here after X-EGROUPWARE-UID and to get optional X-EGROUPWARE-QUANTITY
-					if (!$uid) $uid = groupdav_principals::url2uid($attributes['value']);
+					if (!$uid) $uid = groupdav_principals::url2uid($attributes['value'], null, $cn);
 
 					// try to find an email address
 					if (!$uid && $email && ($uid = $GLOBALS['egw']->accounts->name2id($email, 'account_email')))
diff --git a/calendar/inc/class.calendar_uiforms.inc.php b/calendar/inc/class.calendar_uiforms.inc.php
index 26ef04604a..f5ab7c89b1 100644
--- a/calendar/inc/class.calendar_uiforms.inc.php
+++ b/calendar/inc/class.calendar_uiforms.inc.php
@@ -848,6 +848,10 @@ class calendar_uiforms extends calendar_ui
 		}
 		elseif (($info = $this->bo->resource_info($uid)))
 		{
+			if ($uid[0] == 'e' && $info['name'] && $info['name'] != $info['email'])
+			{
+				return $info['name'].' <'.$info['email'].'>';
+			}
 			return $info['name'] ? $info['name'] : $info['email'];
 		}
 		return '#'.$uid;