If tunnels are not forbidden in the intermediate host, you could use some SSH client (OpenSSH or plink from PuTTY) to create a tunnel from your local machine to the target device telnet port. Then, use Net::Telnet to talk to the remote machine through the tunnel.
in reply to Telnet over SSH2 from Windows
If tunnels are not enabled, you could run netcat or socat in the intermediate machine to obtain a similar effect. I believe that later versions of Perl for Windows already have an emulation of socketpair, so you would be able to do something like...
Net::Telnet ===> socketpair ===> plink ===> netcat ===> destination h
\_______________ ____________/ \___ ___/
Local machine Intermediate machine