Open Solaris is not the same as Solaris, and if anyone attempted forking of Open Solaris they could be sued by Sun for patent infringement, making forking of it very unlikely.
Oops, must not use shorthand or GE will call me on that insignificant fact to derail the discussion.
Your point is that the Chinese get an OS for free. They can do that with OpenSolaris. And wouldn't you know it, they use Chinese on their web site to promote the open aspect. Go ahead, download a live CD of OpenSolaris and have fun, just like the Chinese can. Make some changes and redistribute, just like the Chinese can.
they could be sued by Sun for patent infringement, making forking of it very unlikely.
The CDDL grants a license for the patents. Forking is allowed. The only legal problem in forking is trademark -- "Red Solaris" probably wouldn't fly with Sun's legal department.