Please note that to automatically replace the existing MTA, use the port 
framework of this package:
	
	cd @PORTSDIR@/mail/zmailer && make replace

This will prepare ZMailer for initial configuration and replace your existing 
transport agent.

Also please note that a "make world" will sever the proper links for 
/usr/sbin/sendmail, /usr/bin/mailq and the likes. If you wish to not build 
sendmail as part of a "make world", add NO_SENDMAIL to the build environment. 
You may do this in /etc/make.conf.