Enable for fastcgi in 'domain feature' is waste option (I will remove from 'domain feature).
Nginx and lighttpd standalone use their fastcgi for handling php-cgi. Apache need mod_fastcgi module for the same purpose.
Between mod_fastcgi, mod_fcgid and mod_suphp module, only mod_fastcgi able 'communicate' to php-fpm (where php-fpm 'communicate' to php-cgi). Another module (fcgid and suphp) still 'communicate' to php-cgi directly.