If you are going to Oz you need an Electronic Travel Authority (ETA) as well. This is equivalent to a visa. Costs AUS$20 (about �8.50) and can be obtained at http://www.eta.immi.gov.au/
I looked through the Oz visa website and can't find a required length of passport (although 6 months is usual), so you could try applying for your ETA and see if the site lets you have it. Once you have filled in the form online, you will know almost straight away if its been granted.
It would be helpful if you named your source Ib24. Like sddsdean I can't find anything on line to back that up. 'I think I read' really doesn't count fopr much
Tourist Visit ETAs are valid for 12 months or until the passport expires, whichever comes first, and permit multiple entries into Australia for a stay of up to 3 months on each visit.