Install Exim from ports

cd /usr/ports/mail/exim
make
make install

Port:   exim-4.22_4
Path:   /usr/ports/mail/exim
Info:   High performance MTA for Unix systems on the Internet
Maint:  sheldonh@FreeBSD.org
Index:  mail
B-deps: libiconv-1.9.1_1
R-deps: libiconv-1.9.1_1 rc_subr-1.16