I know that the iPhone's warranty is valid in the "country of purchase", however, I heard a rumor that Apple opened up the warranty service to be in effect anywhere in North America. Is this true? I ask because I'm looking to have a friend ship me a Canadian iPhone4, but I would not buy it from there if I cannot repair/replace my iPhone in US if something were to happen. If you have an answer, please provide the link of your source, I want official Apple documentation if this is true.