return setof record - strange behavior

Hi everybody. Can anyone enlighten me what's wrong with this function :

CREATE OR REPLACE FUNCTION month_year(mon integer, intv integer, OUT
ro integer, OUT mi integer)
RETURNS SETOF record AS
$BODY$
DECLARE
w record;
cy integer := EXTRACT (YEAR FROM current_date);

BEGIN

FOR w IN
SELECT (CASE WHEN m > 12 THEN cy + 1 ELSE cy END)::integer, (CASE
WHEN m > 12 THEN m - 12 ELSE m END)::integer
FROM generate_series(mon + 1, mon + intv) AS m
LOOP
RETURN next;
END LOOP;

END;

$BODY$
LANGUAGE 'plpgsql' VOLATILE;

SELECT * FROM month_year(10, 5);

Why does it return empty SET ? The amount of rows is correct though ....
I'm running 8.1.4

regards
mk