diff --git a/core/trunk/structure.sql b/core/trunk/structure.sql
index c3b5cec1447b46bbaa8c6c4a3cc0d766e5c8641a..72b2211589d99ea250b9261cf70f851935341da5 100644
--- a/core/trunk/structure.sql
+++ b/core/trunk/structure.sql
@@ -695,7 +695,7 @@ CREATE TABLE af_security
   af_security_id bigint NOT NULL,
   af_security_label character varying(255) NOT NULL,
   group_id character varying(50) NOT NULL,
-  tree_id character(50) NOT NULL,
+  tree_id character varying(50) NOT NULL,
   where_clause text NOT NULL,
   start_date timestamp without time zone,
   stop_date timestamp without time zone,