monarch's comment is spot on. While I use the Net::Telnet::Cisco module I made a quick script just using Net::Telnet. Below is a script that logs into a 3750 switch and performs show clock. the switch's prompt is 3750G>. Without the prompt, the script simply times out.

use Net::Telnet;            # use the telnet module

my $host = '3750g';

my $t = new Net::Telnet (Timeout => 10,
                         Prompt  => '/3750G\>/',
                        );
$t->open($host);
$t->login($user,$pass);

@data = $t->cmd("show clock");

print "data is @data";

$t->close;
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Here is the output of the script: data is 19:21:11.575 UTC Tue Aug 21 2007 I hope you can add the Net::Telnet::Cisco module in the future. It greatly simplifies life if you have a bunch of these to keep track of.