CREATE TRIGGER ON INSERT

Hi all,
i have a problem when creating a trigger on DB2 ver 7.2 on WINDOWS.

I have two tables MOVIMAG and BARCODE, the trigge when INSERT INTO
MOVIMAG
will be UPDATE a MOVIMAG field BARCODE taken the value from the table
BARCODE.

I have write this but doesnt work
==========================================
CREATE TRIGGER DB2ADMIN.TRG_I_BARCODE NO CASCADE BEFORE  INSERT  ON
DB2ADMIN.MOVIMAG  REFERENCING  NEW AS N  FOR EACH ROW  MODE DB2SQL
BEGIN ATOMIC
DECLARE iBARCODE varchar(12);
DECLARE iCODICE varchar(12);

SET iCODICE = (SELECT CODICE FROM N);

SET iBARCODE = (SELECT BARCODE FROM DB2ADMIN.BARCODE WHERE CODICE =
iCODICE);

UPDATE N SET BARCODE = iBARCODE;
END
============================================

ERROR:The db answer DB2ADMIN N undefined obj..

why?
tnx