An early iPhone prototype has made its way onto eBay, complete with a rough beta version of iPhone OS and a second, non-functional unit. The working prototype is said to be in good cosmetic condition, and curiously features a matte plastic screen as opposed to the glass screen found in production units. It’s serial number is YM649xxxxxx, which the seller claims corresponds to a factory in China, manufactured week 49 of the year 2006, and it…