For those of you who are trying to upgrade from PHP 5.2 because your application requires PHP 5.2 or above, you can use this hack to upgrade your web server running CentOS. Since CentOS doesn’t officially support PHP 5.2 officially yet, this could possibly be a great workaround.
Word of caution, this hack has worked fine for me for a new Twitter app site I am making that requires use of PHP 5.2 but if you have non-standard customizations to your server, you might want to test it first.
I’ve also found that JSON library that comes with PHP 5.2 is like 20 times fast