This object provides the expiration status of the X.509
certificate on the application sending the notification.
The notification is sent when the value of this object is
changed from certOK(1) to certGoingExpired(2).
certOK(1) = certificate is OK and is not within the
configured time threshold for going to expire
certGoingExpired(2) = certificate is within the configured time
threshold for going to expire
certExpired(3) = certificate has expired, the current time
is after the certificate's validity notAfter time