Trigger only fires when changing the last one of the attributes listed in UPDATE OF

Hi all,

I have the following trigger definition:

CREATE OR REPLACE TRIGGER CX_TG_REQINV_GR_ATTR_RAU
   AFTER UPDATE OF STATE
   OR UPDATE OF KCS_CONSTRTYPE
   OR UPDATE OF CODE_CONSTR
   OR UPDATE OF PLACE
   OR UPDATE OF DESCRIPTION
   ON REQINV
   REFERENCING NEW AS NEW OLD AS OLD
   FOR EACH ROW
   .....

  Is there anything wrong with it? The problem is that the trigger does not fire unless I change the last of the attributes (DESCRIPTION).

If I exchange the last two lines, the trigger fires only when I change the PLACE attribute.

Maybe I miss something obvious, but the examples in the documentation have the same form.