The pilot of an Airbus A340 aircraft had been given clearance for a runway 01 Laravale 5 standard instrument departure (SID). The SID requires a right turn at 3 miles DME. The aircraft was observed to turn right at less than 2 DME. The pilot was asked if he was flying a 01 Laravale 5 departure, to which he replied 'affirmative'. The aircraft's flight path was 1 NM west of Fishermans Island. At the northern tip of the island the aircraft turned sharply right, and crossed the coast at Manly boat harbour at 4,300 ft. This flight path was much closer in than that normally flown on the Laravale 5 SID, and was due to a high rate of climb and a low ground speed. The normal flight path usually arcs around the Brisbane control zone boundary which is a 7 nm radius. A following departing aircraft had been given a right turn onto a heading of 150 which would have kept it inside the normal SID flight path. When it was noticed that the Airbus was turning sharper than normal, the following aircraft was given a heading to pass behind the Airbus.