Last Thursday Apple released an upgrade to the iPhone firmware (the code that controls the phone operations). Users that had installed unauthorized software, found their new programs unusable. Those who had unlocked their phones to use networks other than AT&T—in violation of their agreement with apple-could not use their phones at all. In other words, their iPhones had been bricked.
Then, a user of the Hackintosh Forum who goes by the screen name KMAC1985 discovered a rather peculiar maneuver: If you hold down the power button and the home button on the phone for 10 seconds, then release the power button, the phone will enter a state that will allow it to restore the 1.0.2 software from a connected computer. (The details are here. For the visual, here is a music video tutorial.)
Users are reporting in forum comments that this can take several hours, and that it works for some phones but not others. (See coverage from The Unofficial Apple Weblog and Gizmodo.)
Apple, iPhone, iPhone Ulock, iPhone Unlocking, AT&T