Hey you all-knowing people! Im new to the iPhone. In fact, I havent bought one yet. I understand the jailbreak and unlock process but Im hard put to figure out the activation thing. Heres my situation: Im going to be traveling extensively in Europe for the next eight months and I will be purchasing local Pay as You Go plans in each country I visit. I will be coming back to the US a hand full of times during this period and will then use the AT&T Pay as You Go plan. For this Im buying a brand new iPhone 4 from a buddy who has an AT&T plan. Im going to jailbreak it and unlock it before I leave the US but how do I best deal with the activation? 1. Should I activate it with my buddys sim card and AT&T account? Or 2. Should I hacktivate it? 3. If I activate with my buddys sim, will the phone then be registered to him? 4. Will activating with my buddy's sim preserve Apple's warranty? 5. Is the activation permanent or can the phone be reset to unactivated at some point? For example: Will a restore also deactivate the phone? I need to make sure it all works flawlessly so I dont get screwed while on the road. Thanks for your input.