Iphone question about jailbreak

[iblog]

Hi all, this might have been asked and answered several times before, but I didn't have time to look through all the threads, so here goes:

I live in Australia, but I have many good friends in the US. If I buy an iphone through the apple website and have it sent to my friends and then to me, is it easy to jailbreak it from there?

I am by no means a computer genious and do not know too much about things like this. Should I easily be able to jailbreak the phone?

Will the warranty on the iphone be void if you jailbreak it?

Will the advanced voicemail system work in australia (where you can choose which message you want to listen to first)?

Is it worth it getting the extended warranty?

Thank you for your help!

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