If you know, please reply in the comments section. It would be great to find if more naked pictures of him are out there.
With that, and not to sound cynical, but I'm wondering if perhaps this might be Photoshopped. The crotch area looks a bit off in terms of colors and shadows. Perhaps in the original picture he's shirtless but with pants, and a Photoshop-savvy lad decided he should do the fully monty.
I ran the picture through Google's image search to see what turned up but only found a few blogs with the image but no identification. If you'd like to see in the original larger size, click here.