Can Zend Optimizer and IonCube co-reside on the same server?

[Sorrento]

We have a Windows 2008 server that already has Zend Optimizer installed but have been asked by a user if we can install IonCube?Can Zend Optimizer and IonCube co-reside on the same server?What are the correct directives to use to make this work in the \[code\]php.ini\[/code\] file?We're running PHP 5.2.14 non-threadsafe build.