I threw a quick echo bot together using Net::OSCAR and it worked like a charm.

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

use Net::OSCAR qw(:standard);

sub im_in {
    my ($self, $sender, $message, $is_away) = @_;
    print "$sender: $message\n";
    $self->send_im($sender, "ECHO->$message");
}

my $aim = Net::OSCAR->new();
$aim->set_callback_im_in(\&im_in);
$aim->signon('darwin256','********');
while(1) {
    $aim->do_one_loop;
}
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