According to the courier-mta documentation, courier can use either gdbm or berkeley db:
"The Courier mail server requires either the GDBM or the DB database library. GDBM is used if both are present. This option forces the selection of the database library." ( http://www.courier-mta.org/install.html#configure )
Is there any reason why the Gentoo ebuild forces gdbm to be used ( --with-db=gdbm )?
Created attachment 257311 [details, diff]
berkeley db support for courier ebuild