For more information about what it takes to be a "real" Unix... look at the following page. http://www.unix.org/version3/
This is the updated standard all systems must conform to if they want to be Unix 3 compliant. Then they pay (huge megabucks) and get certified that they meet this standard... and they can be called Unix. The old one (Unix 98) is where most commercial Unix products fall today. I don't know if any have got the updated certification.