diff --git a/user.inc.php b/user.inc.php
index 40a59ffd..59dc0003 100644
--- a/user.inc.php
+++ b/user.inc.php
@@ -858,7 +858,7 @@ function user_valid_user($user)
 	 * Find any character that doesn't match the valid username characters
 	 * (^ inverts the matching remember
 	 */
-	$x = preg_match('/[^a-zA-Z0-9@.-_]/', $user);
+	$x = preg_match('[^a-zA-Z0-9@.-_]', $user);
 
 	/* If x==1, a match was found, and the input is bad */
 	return ($x == 1) ? false : true;