Make sure your handler looks like in the first reply and make sure it comes after mod_mime - this is most likely a handler issue:
LoadModule mime_module modules/mod_mime.so
Mod_mime is required to actually use the handlers.
You should get a warning if it can't find mime.types (a dependency of the above module), but you might do a
find / -name mime.types and copy this file into your /etc/httpd/conf/ directory.
You can make sure it's looking in the right place for the mime types by setting this TypesConfig directory:
You can also see if you have any luck adding these lines:
AddType application/x-httpd-php .php
AddHandler application/x-httpd-php .php
(The Type is more important for client requests.)
A simple test to see if you have PHP with mostly defaulted settings, is to go to a nonexistant page on your server thus generating a 404 error. It should tell you at the bottom something along the lines of
The requested URL /test was not found
on this server.
Additionally, a 404 Not Found error
was encountered while trying to use an
ErrorDocument to handle the request.
Apache/2.2.14 (Unix) mod_ssl/2.2.14
Notice the PHP/5.2.11 in this listing....