make install
===>  Installing for postfix-2.2.10_1,1

===>  postfix-2.2.10_1,1 conflicts with installed package(s):
      courier-0.53.2

      They install files into the same place.
      Please remove them first with pkg_delete(1).
*** Error code 1

Stop in /usr/ports/mail/postfix.
*** Error code 1