As reported by airsecurity.com....nice to know that Quantas is serious about safety.

Australia (Country threat level - 3): A man with known mental issues was allowed to board a domestic Qantas flight at Sydney Airport bound for Wellington on 23 June 2004, despite requests by police authorities that he be barred from the flight. Police made the request after airport staff discovered a note in a terminal restroom written by the man, threatening "Wrath of the Almighty" if he were to be allowed to board the flight.

Qantas officials discovered the signed note in a restroom inside terminal three. Police officials were notified of the threat, and asked that the man be detained until they could arrive. Airline checking attendants refused, and allowed the man to board with an upgraded ticket, citing the fact that he was a frequent flier and known to the staff, who did not deem him a security threat. Airline officials have assured police and Australian Security Intelligence Office agents that future incidents will be dealt with appropriately.