The build-up to the iPhone 5 Sept.12 alleged debut is awash with leaks. Jimmy Lin, a Taiwanese popstar turned race car driver, has spilled the beans on the next-generation Apple smartphone.

Jimmy Lin, who is tremendously popular in China, evidently received a factory mockup of the smartphone and let the details slip on Weibo, a Chinese social networking site.

"Today I can confirm that the upcoming iPhone 5 will be longer and will have aluminum back like the iPad. With its four-inch screen and thin body it feels about the same in the hand [as iPhone 4S did]. The iPhone 5 doesn't use the standard 30-pin dock connector; instead Apple put a smaller 19-pin connector," read the post.

Lin also shared a series of photographs of the purported Apple smartphone, which show him holding and using the device. The images validate Lin's assertions that the iPhone 5 is noticeably bigger than its predecessors. The images also indicate that the smartphone has an aluminium backplate and the rumored smaller docking port. A 3.5mm earphone socket can be espied on the bottom of the device, which is also in keeping with the floating rumors.

Lin hinted that Apple offered him its latest smartphone prior to the official launch. The leaked images have garnered a lot of attention, attracting over 100,000 comments and "more than 80,000 reposts just five hours after being sent."

However, the authenticity of the leaked device remains questionable and experts judge that it is a high-quality fake.

According to TNW "Given the irregularities in the font on the back of the phone and its cheap-looking bottom, the device is almost certainly a fake, though it does bear a resemblance to low-quality factory mockups that appear to be cropping up elsewhere."