http://support.apple.com/kb/ht1937
Click Asia-Pacific and look at Australia. It says, "Carrier offers
authorized unlocking".
I would be very surprised if they would unlock an AT&T iphone. Don't count on this unless you contact the Australian carrier and have them confirm the unlock. I think they can only unlock iPhones sold in Australia.
I have several iPhones including 2 with AT&T for use in USA and a couple with Telstra in Australia. I had no luck getting my AT&T iphones unlocked in Sydney.
this from the Vodaphone site in Australia...
Vodafone can only unlock devices purchased from a Vodafone outlet in Australia.
Your device may be locked to the Vodafone Australia network. If you wish to use your mobile on other networks, Vodafone will supply your device unlock code.
There may be a charge associated with unlocking your device.
The unlock code can be obtained online via the vodafone.com.au/unlock website or by calling Vodafone on 1555 or dialling 1300650410 and selecting the device unlock option. Both options require you to have a credit card to make the payment. Accepted cards are Visa, MasterCard, AMEX, Diners.
Issues Unlocking?
If you experience any issues once the Handset Unlock instruction page is presented, please click on the grey 'Difficulties' button to submit your issue for resolution by the Unlock team.
By requesting to have your device unlocked online you'll save $25 on any unlocking fees.
The unlock fee is structured as follows for devices:
A basic fee of $50 to unlock the device at any time, reduced to $25 if you obtain your unlock code using Vodafone's website at vodafone.com.au/unlock. Plus additional $50 to unlock your device within six months of purchase.
See below for Apple® iPhone™ 3G Unlocking.
If Apple® iPhone™ 3G is less than 6 months old and if:
Unlock is via self-service on website, the charge is $75 dollars
Customer care completes unlock request, the charge is $100 dollars
If Apple® iPhone™ 3G is Older than 6 months and if:
Unlock is via self-service on website, then charge is $25 dollars
Customer care completes unlock request, the charge is $50 dollars
For Prepaid Mobile Broadband Customers:
If you unlock your Prepaid Mobile Broadband device online within the first six months of purchase, your unlock fee will be $75.
If you unlock your Prepaid Mobile Broadband device online at any time after the first six months of purchase, your unlock fee will be $25.
Please Note: The Blackberry Storm is locked to the Vodafone network and cannot be unlocked.