SMTP Messaging Error in Red Hat Satellite 5.8

Issue

• In a Red Hat Satellite 5.8 environment, the Satellite server fails to forward mail to the SMTP server with the following error:

2017-11-03 11:57:32,411 [RHN Message Dispatcher] WARN  com.redhat.rhn.common.messaging.SmtpMail - MessagingException while trying to send email: javax.mail.SendFailedException: Send failed;
  nested exception is: 
    javax.mail.MessagingException: Connection refused (Connection refused);
  nested exception is: 
    java.net.ConnectException: Connection refused (Connection refused)
2017-11-03 11:57:32,411