Best way to protect my new commercial software.

[farsheed]

Let me be clear for you: there are someone in my company who love to
use my software in other companies that she works there also. and
because it is an inhouse tool, my CEO wanted me to protect it from
stealing.
and really we havn't time to copyright it. so I want to secure my
software from some people who love to steal and use it. I am an
animator and 3d programmer, what I wrote is some fast technology for
calculating sub surface lightning (SSS) using mental ray and
renderman. indded this tool works with maya and 3delight and mental
ray standalone. very complicated process and took me tree months to
wrote it. I am not a python pro, I know C++, maya Api, mel,... but I
use python because it is really faster than all of them. hope you
understand why I want to protect it, even if it will slower.