diff --git a/addressbook/inc/class.addressbook_sql.inc.php b/addressbook/inc/class.addressbook_sql.inc.php
index 4741fb2e74..9908fe65d9 100644
--- a/addressbook/inc/class.addressbook_sql.inc.php
+++ b/addressbook/inc/class.addressbook_sql.inc.php
@@ -360,6 +360,12 @@ class addressbook_sql extends so_sql_cf
 				$table = $matches[1] == $this->extra_value ? $this->extra_table : $this->table_name;
 				$extra_cols[] = $table.'.'.$matches[1];
 				$extra_cols[] = $table.'.'.$matches[1]."<>''";
+				//_debug_array($matches[1]);
+				if (!empty($order_by) && $matches[1] != 'extra_order.contact_value' && stripos($matches[1],'.')===false) // postgres requires explizit order by
+				{
+					$order_by = str_replace($matches[1],'egw_addressbook.'.$matches[1],$order_by);
+				}
+				//_debug_array($order_by);
 			}
 		}
 		// add join to show only active accounts (only if accounts are shown and in sql and we not already join the accounts table, eg. used by admin)