CopyObject Error 635

Hi,

I have a function like this :

CREATE FUNCTION calculPeriodesPourAccords()
RETURNS INT2
AS 'DECLARE
lrec RECORD;
lrec2 RECORD;
lint_id_regie INT4;
lint_num_campagne INT4;
lint_num_periode INT4;
ldt_date_trt TIMESTAMP;

BEGIN

ldt_date_trt := now();

-- On d�sactive toues les accords
UPDATE accord_editeur
SET affichage_possible = 0;

FOR lrec IN SELECT id_regie,
num_campagne,
num_periode
FROM periode
WHERE date_debut_periode <= ldt_date_trt
AND date_fin_periode > ldt_date_trt
AND nb_affichage < (max_affichage * 0.9)
AND nb_clic < (max_clic * 0.9)
LOOP
lint_id_regie = lrec.id_regie;
lint_num_campagne = lrec.num_campagne;
lint_num_periode = lrec.num_periode;

FOR lrec2 IN SELECT num_publicite
FROM publicite
WHERE date_debut_publicite <= ldt_date_trt
AND date_fin_publicite > ldt_date_trt
AND id_regie = lrec.id_regie
AND num_campagne = lrec.num_campagne
LOOP

UPDATE accord_editeur
SET affichage_possible = init_affichage_possible,
num_periode = lint_num_periode
WHERE id_regie = lint_id_regie
AND num_campagne = lint_num_campagne
AND num_publicite = lrec2.num_publicite;

END LOOP;

END LOOP;

VACUUM accord_editeur;

RETURN 1;
END;'
LANGUAGE 'plpgsql';

And, when I run it I've got the following error message :

ERROR: copyObject: don't know how to copy 635

What does it mean ?

Thanx,

Guillaume.