On our servers, we run PHP as a CGI script. This is more secure than running it as an Apache module, as PHP running as an Apache module will have the same user rights as Apache does on the server.
Because PHP is running as a CGI script, this means that php_value directives in your .htaccess files will not work. Additionally, adding directives such as AddHandler .php x-httd-php will break your PHP scripts.
We do allow local php.ini (or php4.ini) files. You can use these plain-text files to create PHP directives that apply to the scripts in the same directory and subdirectories therein.