Here are examples of emails and phishing scams...
there is even one there that says...the person made a mistake on their tax return
I suggest you look closely at this page, with examples of how it appears to match the ATO website and so appear legit
http://www.ato.gov.au/onlineservices/content.aspx?menuid=41675&doc=/content/62347.htm&page=7#P303_15052
