I tried this and it doesn't change a thing, I run into the same problem... Argh!

#!/usr/bin/perl -w

use strict;
use IO::Socket;

my ($host, $port, $handle, $byte);

unless (@ARGV == 2) { die "usage: $0 host port" }
($host, $port) = @ARGV;

$handle = IO::Socket::INET->new(Proto     => "tcp",
                                PeerAddr  => $host,
                                PeerPort  => $port);
unless ($handle) { die "cannot connect to mail server on $host" }

$handle->autoflush(1);

print "[Connected to $host:$port]\n";

print $handle "ETRN mydomain.com\nQUIT\n";

while ( <$handle> ) { print }

close $handle;
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