Sorry I am making a bug for two packages in one report, however, it's the same bug so it makes sense, when trying to emerge acct-user/mail or acct-user/postmaster in a crossdev environment they will both fail for the same reason. acct-user/mail: chown: invalid group: ‘root:mail’ * ERROR: acct-user/mail-0-r3::gentoo failed (preinst phase): * fowners failed acct-user/postmaster: chown: invalid group: ‘root:mail’ * ERROR: acct-user/postmaster-0-r3::gentoo failed (preinst phase): * fowners failed Both packages try to chown /var/spool/mail with root:mail, however, even though they have acct-group/mail in their RDEPEND, it isn't replicated in their BDEPEND meaning it never gets merged on the cross host therefore from it's perspective the group doesn't exist causing chown to fail.
It should probably be in IDEPEND, not BDEPEND. I also wonder if we should handle this in the eclass instead of individual ebuilds.
Ah, this is an eclass bug that triggered only when ACCT_USER_HOME_OWNER is set in the ebuild.