On September 19th, Apple announced a voluntary recall and replacement program for the USB power adapter that shipped with the iPhone 3G. According to the iPod Observer, replacement units have begun to ship for users who ordered them online. Replacements will also be available in Apple retail store locations come October 10th.

For users sending the original units back, Apple requires that the old adapter be shipped back within ten business days or the customer's credit card will be charged. For those who visit an Apple retail store, they'll need to bring their iPhone 3G and the old power adapter.

The company said that the old adapter prongs, in some cases, could break off within the electrical socket leading to possible shock. Updated power adapters can adapters can be readily identified by a green dot on the plug side.

If your replacement power adapter has shipped or you've seen the issue with the prongs on the original units, please let us know in the comments or forums.