Maybe as an alternative, consider sending back want is being requested, i.e. a response. That should cause the rest of the output to be delivered.
It's mentioned quite often in the
Net::Telnet documentation to use
print() and
waitfor() when the
cmd() function does not do what you want it to.
Since the carriage feed is added automatically, try just sending back any character.
As an example... (note this is untested)
$string = "show";
$thost->print($string);
$thost->waitfor('----More---')
$anykey = "b";
$thost->print($anykey);