This could be really big.
Read about it hear.The source, who has seen both the Unix System V source code and the Linux source code and who assisted with a SCO project to bring the two kernels closer together, said that SCO "basically re-implemented the Linux kernel with functions available in the Unix kernel to build what is now known as the Linux Kernel Personality (LKP) in SCO Unix."
http://www.eweek.com/article2/0,3959,1123176,00.asp