about 5th day tickets for the tests mate...
i think you'll find most places sell these on the day, rather than in advance (like the first 4 days) on the basis that not many tests get to a fifth day, especially with the aussies. the best bet, if a fifth day is probable, is just get there early on the day.
i might be wrong, but hope that helps.
Cheers for that, anybody got a tent i can borrow?