mySQL: EXCEPT

Vi har problemer med at traekke to SELECT-statement fra hinanden;

(SELECT place, wagonId FROM Furniture WHERE isWindowSeat IS NOT NULL)
EXCEPT
(SELECT furnitureReservationPlace AS place, furnitureReservationWagonId
AS wagonId FROM ETickets WHERE furnitureReservationPlace IS NOT NULL AND
furnitureReservationWagonId IS NOT NULL)

Men vi faar en fejl pga. EXCEPT. Er det korrekt, at EXCEPT ikke
eksisterer i mySQL 4.1.20? Hvordan kan man ellers gore?