Refuse to talk to yourself (i.e., reject HELO packets with your own name).

Add two thresholds -- option 'x' is the load average at which messages are
queued rather than delivered (default 12); option 'X' is the load average
at which incoming TCP connections are refused (default 25).

SCCS-vsn: usr.sbin/sendmail/src/conf.c 4.2
SCCS-vsn: usr.sbin/sendmail/src/main.c 4.2
SCCS-vsn: usr.sbin/sendmail/src/deliver.c 4.2
SCCS-vsn: usr.sbin/sendmail/src/daemon.c 4.4
SCCS-vsn: usr.sbin/sendmail/src/savemail.c 4.2
SCCS-vsn: usr.sbin/sendmail/src/srvrsmtp.c 4.3
SCCS-vsn: usr.sbin/sendmail/src/version.c 4.7
SCCS-vsn: usr.sbin/sendmail/src/readcf.c 4.2