"A holder of a valid foreign ATPL licence that has been issued by an ICAO Contracting State, may convert this licence to an Australian ATPL. The conversion requires passes in both the CPL Flight Rules & Air Law exam for the relevant aircraft category and the ATPL Air Law exam (AALW).
It is also a requirement to hold a multi engine command instrument rating for the issue of an aeroplane ATPL. This requires a pass in the IREX exam and the instrument rating flight test."
Easily found on the CASA web site.