There lack of Officially listed FOSS accountancy package for Australia.
As you can see here http://softwaredevelopers.ato.gov.au/viewproductregister

There is 46 currently listed test requirements to be listed.
http://softwaredevelopers.ato.gov.au/testscenarios to be listed. You will need cookies enabled to access this site.

This is where Australian Accountants look for software to recommend to customers. Does bring some testing requirements.