gistfile1.perl

#!/usr/bin/env perl
use strict;
use warnings;
use IM::Engine;

IM::Engine->new(
    interface => {

#        protocol => 'Jabber',
#        credentials => {
#            jid      => '...',
#            password => '...',
#            host     => 'jabber.org',
#        },

#        protocol => 'AIM',
#        credentials => {
#            screenname => '...',
#            password   => '...',
#        },

        protocol => 'IRC',
        credentials => {
            server   => 'irc.perl.org',
            channels => ['#im-engine'],
            nick     => '...',
        },

        incoming_callback => sub {
            my $incoming = shift;

            my $message = $incoming->message;
            $message =~ tr[a-zA-Z][n-za-mN-ZA-M];

            return $incoming->reply(
                message => $message,
            );
        },
    },
)->run;