It was confirmed by the source, Splash News, that it was their party and their paps giving it. And he moved to the other side of the planet after this happened.
More like, country, as in Brooklyn.
He and Michelle lived in Australia for the first 6 months of 2005, while he was filming "Candy" and she was pregnant with Matilda. At that point, their plan was to divide their time equally between the US and Australia. However, after the Australian premiere of Brokeback Mountain, when he was squirted with squirt guns, he immediately put his Australian home on the market and it sold in four days. He said at that time he had no intention of ever living or working in Australia again for an extended period of time--unless the paparrazzi situation changed significantly. In fact, I think I read somewhere that Heath was on the Baz Luhrman's short list for the lead in "Australia" and when he heard Heath say this, he crossed him off, knowing that the filming would be months-long (it ended up taking 9 months in all) in Australia.
The Australian premiere of BBM was January 10, 2006 in Melbourne. I think it premiered in other cities, too.
L