"He's rehabing well and he won't be far away, but the reality is he probably won't be ready," said Australia head coach Robbie Deans.
The 25-year-old Waratahs star still hopes to make the trip to Europe but insists he won't put himself forward for selection unless he is 100-per-cent fit.
''It's all still in sight for the spring tour," said Polota-Nau, somewhat optimistically.
"I've ruled out any possibility of going with an 85 per cent fitness tolerance.
"Robbie Deans has given me the leniency to say when I'm right or not."
Polota-Nau is currently battling for the hooking spot with veteran Stephen Moore and Queensland Reds youngster Saia Faingaa.
The Sydney-born No2 has represented Australia at all levels from schoolboy to senior, making his full debut in 2005.
He became one of a select band of players to make his international bow before playing Super 14 rugby when he lined up against England at Twickenham that November.
Australia face the All Blacks in Hong Kong on October 30 before facing Wales, England, Italy and France on successive Saturdays, with mid-week matches against Leicester Tigers and Munster also part of their schedule.