The following error occurs during RBL server adding:
CauseImproper hostname configuration.
ResolutionMake sure that /etc/hosts contains the records in the following format:
192.168.1.10 foo.mydomain.org foo
Where 192.168.1.10 should be replaced with the server IP and foo.mydomain.org with the real server hostname. How to get or change the hostname can be found in the 1793 article.