Zend/Ioncube???

I have just had installed the Zend optimizer on my server for another application.
I understand that PHPRunner does not use Zend - but does it require Ioncube - or anything special? My first reaction to the installation of the optimizer is that the server now responds mores slowly to my PHPRunner-generated programs than before- but that could be due to other factors, including connectivity issues.
I would appreciate any feedback
Andrew