If my memory serves me correctly the crew that did not put the CTP on the 737 from Per to Syd had done the CGK BOC the night before. Fatigue was considered to be a contributing factor. It was also considered to be a CF in the 737 EGPWS event near CB in 2005. I'm sure the public would love to know that the "princesses" up front are legally allowed to sleep in the cockpit just to try and mitigate the potential for a disaster at the end of the duty.