Resellers have begun selling unlocking software for the Apple iPhone. 

The U.S. company, iPhoneSIMFree, is offering the unlock to iPhone users, in which the SIM card in the iPhone is unlocked so that carriers other than AT&T (currently the only U.S. iPhone carrier) can be chosen for making iPhone calls, is reportedly charging US$99 for the service.  Resellers iPhone Worldwide Unlock, an Australian Web site, is offering the unlock hack for $50 and claims that it already has 1,000 orders, while a German reseller is also offering the hacking unlock for $50. 

Reseller Wireless Imports is also offering the hack, but claims to be waiting on the licensing unlock from iPhoneSIMFree.  All of the resellers reportedly are taking pre-orders only at this time.

All of the resellers offering the unlocking service are disclaiming any guarantees as to how long the unlock will be effective, since the unlock may not survive the next Apple iPhone update. They also are advising customers that if the iPhone is locked again the customer will have to pay a separate fee again to unlock it. Previously, Apple's iPhone updates required customers who hacked or modified their iPhones to erase the modifications as a prerequisite to installing the next iPhone update.

Apple did not indicate whether it will take steps to relock its iPhone in firmware updates or whether it will proceed legally against the companies and resellers that are selling the iPhone software hacks.