I only take pop3 for example. Actually any protocol which are right in command line use can not work correctly in my apache cgi environment . Like this 80 port:

#!/usr/bin/perl
use strict;
use warnings;

use IO::Socket;

my $http = IO::Socket::INET->new(
            PeerAddr => "mail.163.com",
            PeerPort => 80,
            Proto    => 'tcp',
            Timeout  => 20 );
print "Content-type: text/html\n\n";
print "Result: ";
print $http;
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