As Chris Jones briefly mentions and this press release discusses in more detail, Zend and Oracle have joined together to make it even easier for those using Oracle to also use Zend Server as their platform.

This is a first step to making it easy for our customers and users to quickly deploy the Zend software stack without having to go to various websites, download various packages and install them. [...] We now host an rpm package on the ULN [Unbreakable Linux Network] servers called zend-server-repo which updates the Linux OS install to also look at the software repositories hosted by Zend. When a user wants to install Zend Server, just a simple command will install the zend-server product directly.

They've also added it as a package for those using the Oracle Enterprise Linuxyum-installable package. You can find out more of the technical details on the Oracle Technology Network.

Zend's press release can be found here.