dkim-milter and postfix permission denied

[Clodoaldo Neto]

When using dkim-milter with postfix i get this error:

warning: connect to Milter service
unix:/var/run/dkim-milter/dkim-milter.sock: Permission denied

It works if I include postfix in the dkim-milter group AND chmod the
socket file to allow the group to write to the socket:

# usermod -a -G dkim-milter postfix
# chmod o-w dkim-milter.sock

The problem is that when the dkim-milter service is restarted it
restores the socket file permission to 755 which breaks postfix.

This is the /etc/init.d/dkim-milter line starting the service:

daemon --user ${user} ${prog_with_path} -x ${config} -P ${pidfile} -p
${SOCKET} ${EXTRA_FLAGS}

How to definitely solve it?

Regards, Clodoaldo