Derick Rethans has a new post today looking at a method for setting up multiple PHP versions on the same machine and switch between them with a little help from some simple bash scripts.

For many of my projects (both hobby and commercial) I need to support many different PHP configurations. Not only just different PHP versions, but also debug builds, ZTS builds and 32-bit builds. In order to be able to test and build extensions against all those different PHP configurations I have adopted a simple method that I'm sharing with you here.

Using this script he can tell his system to pull the latest version of any release from SVN and try to compile it. The trick is putting each of them into a different directory under /usr/local. He uses another small shell function (with a function called "pe()") that sets up the pathing to the right release, complete with its own locations for PEAR/PECL and a php.ini.