Look at the bottom right of his "skirt" thing. It is obviously photoshopped. Whether that is the only part that is, I do not know. But it has obviously been tampered with.
Whether or not some sick individual altered the photo of a very ill man (and I'm still waiting on Chausey's certification that it's fake...) here's a most remarkable speech by Steve, his 2005 Stanford Commencement Address. Well worth 15 minutes of your life. http://www.youtube.com/watch?v=UF8uR6Z6KLc
You would think TMZ has plenty of experience with potentially fake photo's so I would think for them to post this they are saying this is 100% real. I'm sure whoever took it is closely afiliated with these celeb websites. IMO.