Apache error for undefined symbol in libphp5.so

Good morning, I recently compiled and installed Apache 2.0.59 and PHP 5.2.1 on a virtual Fedora Core 4 server and all went well until I decided to enable more extensions in my PHP install. When trying to start Apache after the re-build of PHP I received a syntax error noting an undefined symbol "zend_ini_string" The first time it said "php_write" was the undefined symbol, then "zend_ini_string", and something else randomly depending on what I have in my config statement. I've been working to delete and re-install everything, wanted to know if anyone knew why this would be going on - I'm figuring its not "zend_ini_string" but moreso libphp5.so or something else with Apache? First time doing much of anything on a Linux box, but I'm working on it! Much thanks, -Andy