Was looking at all this a few years back, and the advice I got from most of the accountants I contacted was as 43 Inches stated, although one guy said it would be fine for me to claim. I guess it depends on who you get your advice from.
I was told the safest way would be to obtain a private ruling, the only problem would be if it didn't go the way you wanted it would set a precedent against the people who have already claimed it.
Sure enough claim it, but i would be prepared to pay it back if you get audited. Just because your tax gets through doesn't mean the ATO is ok with it, I was audited over a minor allowances issue (luckily nothing came out of it) that took place 2 years prior! I aren't sure but i don't think you are safe for 6 years.