OpenDKIM | gentoo | warning: connect to Milter service unix:/var/run/opendkim/opendkim.sock: No such file or directory

On Gentoo some postfix processes run chroot’ed but others do not. In result these processes need different sock locations, but this is impossible.
Solution:

 # mkdir -p /var/run/postfix/var/run/opendkim
 # chmod milter:milter /var/run/postfix/var/run/opendkim
 # usermod -a -G milter postfix
 # mount --rbind /var/run/opendkim /var/run/postfix/var/run/opendkim