In Reply to: phones posted by paula on Friday, 13. July 2007 at 09:51 Bali Time:
International roaming is only needed if you want to use your home sim card in another country, ie it is not trying to connect to, for example, Telstra network, it is roaming to find a compatible network overseas. It is often very expensive to use International roaming.
Your phone must not be locked to your network at home. You might like to ring your provider in Australia to check if its locked or not, and have it unlocked if necessary.