diff --git a/addressbook/inc/class.addressbook_so.inc.php b/addressbook/inc/class.addressbook_so.inc.php
index 7f126f5307..d76d1fff02 100755
--- a/addressbook/inc/class.addressbook_so.inc.php
+++ b/addressbook/inc/class.addressbook_so.inc.php
@@ -352,7 +352,7 @@ class addressbook_so
 	 */
 	function read_customfields($ids,$field_names=null)
 	{
-		return $this->soextra->read_customfields($ids,$fieldnames);
+		return $this->soextra->read_customfields($ids,$field_names);
 	}
 
 	/**