command line - How would you configure byobu as a login shell?

I need to have my telnet and ssh users use byobu as their login shell.
I would like to avoid using .login/.profile/.bashrc and the likes to spawn byobu.
I'd like to have byobu as the shell defined in /etc/passwd.
I've already done a few tests, but have been unable to have it working properly.
Any idea?