SysAdminGear

eAccelerator description:
"eAccelerator is a free open-source PHP accelerator, optimizer, and dynamic content cache. It increases the performance of PHP scripts by caching them in their compiled state, so that the overhead of compiling is almost completely eliminated. It also optimizes scripts to speed up their execution. eAccelerator typically reduces server load and increases the speed of your PHP code by 1-10 times." (Font: eAccelerator )

eAccelerator auto installer should work perfectly on any cPanel server, there are lots of sanity checks built in to prevent any possible issue or destruction.

Download and run eAccelerator autoinstaller:
# wget http://tutorials.medialayer.com/cPanel/eaccelerator.sh
# chmod 700 eaccelerator.sh
# ./eaccelerator.sh

Note: The php.ini gets backed up before it is modified, you can get it back..