Iphine in Apple Store simlock and netlock free?

I want to buy my son, who is studying in Sydney an Iphone 3GS in the Apple Store in Sydney. As he will return to Europe in December 2010, I want to buy an IPhone without a long lasting contract and one which he can use in Europe when he comes back.
My Question:
Is the Iphone 3GS, which can be bought in the Apple Store in Sydney, simlock and netlock free?