diff --git a/lib/SimpleSAML/Auth/LDAP.php b/lib/SimpleSAML/Auth/LDAP.php
index 91cb29717636b8f11462abec73ebf095f7761484..fe523bec4113e831d53e8be366b1ddcb7462c522 100644
--- a/lib/SimpleSAML/Auth/LDAP.php
+++ b/lib/SimpleSAML/Auth/LDAP.php
@@ -130,7 +130,7 @@ class SimpleSAML_Auth_LDAP {
 	/**
 	 * Search DN for attributes, and return associative array.
 	 */
-	public function getAttributes($dn, $attributes) {
+	public function getAttributes($dn, $attributes = null) {
 	
 		$searchtxt = (is_array($attributes) ? join(',', $attributes) : 'all attributes');
 		SimpleSAML_Logger::debug('Library - LDAP: Get attributes from ' . $dn . ' (' . $searchtxt . ')');