Bitrot: API for the ersatz inet_ntop() function, when
compiling with -DNO_IPV6 (which exists only for debugging).
Files: util/sys_defs.h, util/sys_compat.c.

Feature: smtp_tcp_port, similar to the existing lmtp_tcp_port.
Files: mantools/postlink, proto/postconf.proto,
global/mail_params.h, smtp/smtp.c, smtp/smtp_connect.c,
smtp/smtp_params.c.

Feature: "PASS" and "STRIP" actions in header/body_checks.
"STRIP" is similar to "IGNORE" but also logs the action,
and "PASS" disables header, body, and Milter inspection for
the remainder of the message content.  Contributed by Hobbit.
Files: cleanup/cleanup_message.c, global/header_body_checks.c.