Improved SCGI security:
(1) The --scgi option only listens on IP address The new
--remote-scgi option must be used if the webserver is on a different machine.
(2) The new --fromip option can be used to restrict incoming requests to
a particular IP address.
(3) In SCGI mode, the new parameter "SERVER_ADDR" contains the IP
address of the webserver that originated the SCGI request.