# require socat *2* !!!
socat tcp-listen:6666,reuseaddr 'system1:"perl -CI recode.pl 1" % system1:"perl -CO recode.pl 0" | tcp:irc.friend-chat.jp:6667'

# in irssi
/connect localhost 6666

# save as recode.pl:
#!/usr/bin/perl -lp
use Encode qw(encode decode);
BEGIN { $|++; *z=shift()?*encode:*decode }
$_ = z("iso-2022-jp", $_)


# or with automatic decode guess:
#!/usr/bin/perl -lp
use Encode qw(encode decode);
use Encode::Guess;
BEGIN {
    $|++;
    my @enc = qw(euc-jp shiftjis 7bit-jis);
    *z=shift()?sub{$_=encode("iso-2022-jp",$_)}
    :sub{
        my $enc = guess_encoding($_,@enc);
	$enc = do {
	    local $Encode::Guess::NoUTFAutoGuess=1;
	    guess_encoding($_,@enc)
	} unless ref $enc;
	$_ = $enc->decode($_) if ref $enc;
    }
}
z()