my $ssh = Net::OpenSSH->new('user@1.1.1.2');
my ($socket, $pid) = $ssh->open_tunnel('1.2.0.1', 23);
my $telnet = Net::Telnet->new(-fhopen => $socket,
                                -prompt => '/.*\$ $/',
                                -telnetmode => 0,
                                -cmd_remove_mode => 0,
                                -output_record_separator => "\r");
$telnet->waitfor(-match => '/login\ name\:/',
                   -errmode => "return")
    or die "login failed: " . $telnet->lastline;
my @lines = $telnet->cmd("who");
print Dumper(@lines);
$telnet->close;

##</code><code>##

or die "login failed: " . $telnet->lastline;

##</code><code>##

login failed:  at test.pl line 21.