I'm sorry to surface this issue again, but I'm still not getting a good grasp on the best implementation for our situation and I'm hoping to clarify. Understanding that: We have a dedicated server running CentOS Using WHM/cPanel Multiple versions of PHP We have to compile PHP via command line PHP 5.4.21 (latest in the 5.4.x branch) is still shipping with LSAPI 5.5. Clearly there have to be benefits from upgrading LSAPI to 6.4. I've tried downloading 6.4 and unzipping into the PHP source folder as instructed, but that always generates errors during configure/make. What else do I need to do when compiling PHP to make use of the latest LSAPI version?