diff --git a/lam/lib/account.inc b/lam/lib/account.inc
index be64bfce..5affdfa8 100644
--- a/lam/lib/account.inc
+++ b/lam/lib/account.inc
@@ -503,6 +503,9 @@ function get_preg($argument, $regexp) {
 					$pregexpr = '/^[0-9a-zA-Z_-]+(\\.[0-9a-zA-Z_-]+)*$/';
 					break;
 		case 'nis_alias':
+					$pregexpr = '/^([[:alnum:]])+$/u';
+					break;
+		case 'nis_recipient':
 					$pregexpr = '/^([[:alnum:]@\\.\\ \\_-])+$/u';
 					break;
 	}