These are the packages that would be merged, in order:

Calculating dependencies ... done!
Dependency resolution took 1.05 s (backtrack: 0/20).

[ebuild  N     ] net-libs/courier-unicode-2.6.0:0/10::gentoo  691 KiB
[ebuild  N     ] net-mail/courier-common-3.3.0::gentoo  USE="gdbm -berkdb" 2387 KiB
[ebuild  N     ] net-libs/courier-authlib-0.73.2::gentoo  USE="gdbm pam sqlite -berkdb -debug -ldap -mysql -postgres -static-libs" 2705 KiB
[ebuild  N     ] net-mail/courier-imap-6.0.7::gentoo  USE="gdbm ipv6 -berkdb -debug -gnutls (-selinux) -trashquota" 3661 KiB

Total: 4 packages (4 new), Size of downloads: 9443 KiB