suPHP is a tool for executing PHP scripts with the permissions of their
owners. It consists of an Apache module (mod_suphp) and a setuid root
binary (suphp) that is called by the Apache module to change the uid of
the process executing the PHP interpreter.

This version was compiled to look for its config-file in /etc/apache
rather then just /etc as 'httpd' looks there aswell.

Some of the 'standard' /etc/apache/httpd.conf directives include:

  LoadModule suphp_module  /usr/libexec/apache/mod_suphp.so
  suPHP_Engine on
  AddHandler x-httpd-php .php
  suPHP_AddHandler x-httpd-php
  suPHP_UserGroup someuser users

To use different php versions 'per vhost' see:
http://www.howtoforge.com/apache2_suphp_php4_php5

suPHP needs a CGI build of the .php interpreter, usually named 'php-cgi'
implying having to (re)compile PHP with in place of '--with-apxs'

  '--enable-force-cgi-redirect'

Note that it being somewhat slower then mod_php can be redused
(grately) by building for the FastCGI too and using mod_fcgid
however that would need additional configuration, see:
http://fastcgi.coremail.cn/configuration.htm