If you want native JIT code, use this instead.

http://hhvm.com/

hmm.. the last time I looked at this was a seriously long time ago, and was the zend encoder I looked at.

but the way it works is, it's some sort of compiler for your PHP code. not native, but it compiles it into byte code, of which you'll then need to have your web server enabled with their engine to run it in addition to the usual PHP.

at the very base of it, its a byte code compiler. with their engine, you may get some performance improvements. not sure if there's any byte code encryption in place or not though. there might be now.