What is your OS? I just tried your code and it worked: 
dda@x700:/tmp$ perl nt.pl
errmsg: problem connecting to "localhost", port 23: Connection refused
dda@x700:/tmp$ cat nt.pl
#!/usr/bin/perl -w
use strict;

use Net::Telnet;

my $telnet = new Net::Telnet ( Timeout=>10, Port => 23, Errmode=>'retu
+rn');
$telnet->open("localhost");
print "errmsg: " . $telnet->errmsg . "\n";
dda@x700:/tmp$

[download]

--dda

In reply to Re: Trying to capture an error using NET::TELNET by dda
in thread Trying to capture error message using telnet::net by tprizler

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