The pilot submitted a flight plan for a flight from Brisbane Airport to the television studios at Mt Cootha. The flight planned cruising altitude was 1000 feet. When the pilot requested an airways clearance, prior to takeoff, the Surface Movement Controller(SMC) in the Brisbane Control Tower found that the required cruising altitude had not been annotated on the flight progress strip. He therefore issued the aircraft with a clearance at 1500 feet. This altitude was accepted and acknowledged by the pilot. The SMC then advised the Brisbane Approach Controller the cleared cruising altitude of the aircaft. After the aircraft departed, the pilot advised the Brisbane Approach Controller that the aircraft was on climb to a cruising altitude of 1000 feet, in error. This was not queried by the Approach Controller. No traffic conflictions resulted from the occurrence.