SPECIAL INSTRUCTIONS FOR DIGITAL UNIX 4.0B Patch 873.00 
WARNING! Possible System Setup Change Required, syslog Behavior Change
    The security of the syslog facility has been enhanced in this patch.  Unless
    the domain host name of a remote host is entered in the local file,
    /etc/syslog.auth, the local system will not log any syslog messages from
    that remote host.

    If you install this patch (the secure version of syslogd) on a system, and
    you have configured or intend to configure other hosts to forward syslog
    messages to the system refer to the Release Notes or patch README
    documentation for information on how to setup the system.