I have been in Australia since friday and the Galaxy s2 has been doing the job fantastically without having to put an Ozzie sim in it. Today I lost connection to the network, when I tell it to connect automatically it tells me it has (lies) and when I attempt to connect to either Vodafone au or optus (the two it was connecting to) it tells me that it is unable to connect at this time, frustrating. Might have to get the Telstra sim I'm using in my MF60 activated for voice calling.
Have tried rebooting the phone (even removing battery and sim) but no joy. I have logged a job with 2degrees via the help and support website as I have no phone to call them from.
Just get an Aussie SIM and avoid roaming fees. I couldn't connect at all to 2Degrees after arriving in Australia, despite them saying I shouldn't have any problem doing so. Using an Optus SIM I had trouble-free experience while there. It beats spending time messing around trying to get the issue resolved.