MacRumors reports that an iPhone 4 prototype has shown up on eBay running Apple's in-house diagnostics software

A number of high-quality photos are included with the listing, showing a complete lack of Apple branding on the exterior of the device. Most notably, the Apple logo has been replaced with a distinct logo that was previously seen in a Twitpic posting in February 2010. The standard "iPhone" text on the rear of the device has also been replaced by "Prototype", along with text noting that the device has not been approved by the Federal Communications Commission and can not be sold until such authorization is granted.

Sonny Dickson has also provided an overview video of the device showing off several of the features of the device including the software and a lack of screws on the bottom of the device that is consistent with some of the earlier leaked prototypes.

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