diff --git a/phpBB/includes/functions.php b/phpBB/includes/functions.php
index bdc081c593..a483871d3a 100644
--- a/phpBB/includes/functions.php
+++ b/phpBB/includes/functions.php
@@ -2750,7 +2750,7 @@ function get_preg_expression($mode)
 	switch ($mode)
 	{
 		case 'email':
-			return '(?:[a-z0-9\'\.\-_\+\|]|&)+@[a-z0-9\-]+\.(?:[a-z0-9\-]+\.)*[a-z]+';
+			return '(?:[a-z0-9\'\.\-_\+\|]++|&)+@[a-z0-9\-]+\.(?:[a-z0-9\-]+\.)*[a-z]+';
 		break;
 
 		case 'bbcode_htm':