root@kaka:~ sudo apt-get install inetutils-telnetd telnet
root@kaka:~ sudo sed -i 's/#<off># telnet/telnet/' /etc/inetd.conf
root@kaka:~ sudo /etc/init.d/inetutils-inetd start
root@kaka:~ USER='-f root' telnet -a localhost
...
root@kaka:~#
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