...is what I would like to know as to whether or not is possible. I have a second iPhone 3GS in black, which I would like to switch to, and give my white one to my girlfriend. However, it runs 3.1.3, and I can live without the jailbreak for now, but I do need to be able to tether every now and then. I found this step-by-step guide, but it's from before the 3GS was released. I have tethering set up exactly how it is described in this blog, but by downloading this "Tether" informational file from Cydia, which describes the process of unhiding and enabling the iPhone's native tethering capability. The carrier file from this blog looks to be the same or similar to the one jailbreak method. The question is, can I somehow get tethering to work, with or without this carrier file, without having to jailbreak. It describes how to do it with a Mac and iTunes, but I need the Windows method, although if it definitely will work with a Mac, I can boot into OS X if need be, but I'd rather do it in Windows. Can someone please help me with this? That would allow me to give my girl an iPhone, and I'll still be able to get online when I need to by way of tethering. Any help is greatly appreciated!