Today, Apple has issued a recall on the ultracompact USB power adapter that ships along every iPhone 3G, it’s also sold as a standalone accessory. Apple has received reports of the metal prongs breaking off of the adapter and remaining lodged in power outlets, creating the risk of electric shock.

From Apple’s support article:

Apple has determined that under certain conditions the new ultracompact Apple USB power adapter’s metal prongs can break off and remain in a power outlet, creating a risk of electric shock. We have received reports of detached blades involving a very small percentage of the adapters sold, but no injuries have been reported.

Users with ultracompact power adapters should immediately stop using them until they exchange them for a new, redesigned ultracompact adapter.

According to Apple, the adapter was included with every iPhone 3G sold in the US, Japan, Canada, Mexico, Colombia, Ecuador, El Salvador, Guatemala, Honduras, and Peru. The adapter was also available as a standalone accessory in those countries, as well as Argentina, Chile, Costa Rica, and Panama.

These replacement adapters will ship within three weeks of your order, starting on Friday, October 10, 2008

You can exchange the power adapter via the web (links below) or you can exchange it to your local Apple Retail Store starting October 10, 2008.
Apple’s Ultracompact USB Power Adapter Exchange Program

Apple’s Ultracompact USB Power Adapter Exchange Program (Direct link to exchange form)

Apple Retail Store listings