Your output looks doubled. Did you run it twice - once with Alpha($_) uncommented and once with Omega($_) uncommented, or what?

Yes I did , its why the output is slightly different format each time

Just tried it on a different host and the results are 100% negative (i.e. correct). Any ideas?

Just the same ones :) Try adding this and see what you get 

use Mail::CheckUser qw/ check_email last_check  /;
BEGIN{
    $Mail::CheckUser::Skip_SMTP_Checks = 1;
    $Mail::CheckUser::Treat_Timeout_As_Fail = 1;
    $Mail::CheckUser::Debug = 1;
}

[download]

or maybe look inside :) look at what its doing ... so i do that and I try I get 

use Net::DNS::Resolver ;
use Data::Dump;
my $f = Net::DNS::Resolver->new; 
dd( $f->query( q{abczz123ffz.com}, 'MX') );
dd($f);
dd($f->query(q{b.com}, 'MX') );
dd($f);
__END__
undef
bless({
  adflag         => 0,
  answerfrom     => "192.168.1.254",
  cdflag         => 0,
  debug          => 0,
  defnames       => 1,
  dnsrch         => 1,
  dnssec         => 0,
  domain         => "attlocal.net",
  errorstring    => "NXDOMAIN",
  force_v4       => 0,
  force_v6       => 0,
  ignqrid        => 0,
  igntc          => 0,
  nameserver4    => ["192.168.1.254"],
  nameserver6    => [],
  persistent_tcp => 0,
  persistent_udp => 0,
  port           => 53,
  prefer_v6      => 0,
  recurse        => 1,
  retrans        => 5,
  retry          => 4,
  searchlist     => ["attlocal.net"],
  srcaddr        => "0.0.0.0",
  srcport        => 0,
  stayopen       => 0,
  tcp_timeout    => 120,
  tsig_rr        => undef,
  udp_timeout    => undef,
  udppacketsize  => 0,
  usevc          => 0,
}, "Net::DNS::Resolver")
undef
bless({
  adflag         => 0,
  answerfrom     => "192.168.1.254",
  cdflag         => 0,
  debug          => 0,
  defnames       => 1,
  dnsrch         => 1,
  dnssec         => 0,
  domain         => "attlocal.net",
  errorstring    => "NXDOMAIN",
  force_v4       => 0,
  force_v6       => 0,
  ignqrid        => 0,
  igntc          => 0,
  nameserver4    => ["192.168.1.254"],
  nameserver6    => [],
  persistent_tcp => 0,
  persistent_udp => 0,
  port           => 53,
  prefer_v6      => 0,
  recurse        => 1,
  retrans        => 5,
  retry          => 4,
  searchlist     => ["attlocal.net"],
  srcaddr        => "0.0.0.0",
  srcport        => 0,
  stayopen       => 0,
  tcp_timeout    => 120,
  tsig_rr        => undef,
  udp_timeout    => undef,
  udppacketsize  => 0,
  usevc          => 0,
}, "Net::DNS::Resolver")

[download]

So this mean my local DNS server is telling me those adresses don't really exist

Maybe your DNS server is lying to you , it happens, DNS hijacking

In reply to Re^4: Mail::CheckUser inconsistent results by Anonymous Monk
in thread Mail::CheckUser inconsistent results by tel2

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