up to 1.3.0, adds whitelisting support
up to 1.3.1, disable embedded Perl

Note: some blacklister as Spamhaus ban DNS queries from public DNS
resolvers as Google resulting in no host being listed. If you are
experiencing problems with the plugin just try the DNS query with a tool
as nslookup to check your DNS configuration.
1.3.3, parameter validation

using Data::Validate modules
up to 1.3.4
up to 1.3.5