Still, I'll bet they could have used rafts.
The Australian Aboriginals were in Australia about 50,000 BC, and there was never a complete bridge. I think the closest land approach would still require a 26 mile water journey.
The Wallace Line explains it.
Neanderthal Man Floated Into Europe, Say Spanish Researchers
http://www.freerepublic.com/focus/news/1559199/posts
Neanderthals were ancient mariners
http://www.freerepublic.com/focus/chat/2853535/posts
26 miles across the sea?
https://www.youtube.com/watch?v=HJM61CTenss
(please forgive the flippancy )
:-)