sub checkports {
    
    my $sock;
    my ($pop, $smtp, $ftp) = @_;
    DEBUG && print "Checking ports : ";
    my %ports = (
            110 => $pop,
            25 => $smtp,
            21 => $ftp
        );
    
    for my $port (keys %ports) {
        DEBUG && print "[$port] ";
        
        $sock = new IO::Socket::INET(PeerAddr => $ports{$port}, PeerPort => $port, Proto => 'tcp', Timeout=>10);
        if ($sock) {
            $client->{"PORT$port"} = 'U';
            close $sock; 
        } else {
            $client->{"PORT$port"} = 'D';
        }
    }

    DEBUG && print " done.\n";
}