My understanding was the opposite. Two examples I found where backdoor is working are:
env -i LANG=en_US.UTF-8 /usr/sbin/sshd -D
env -i LANG=C /usr/sbin/sshd -h env -i LANG=en_US.UTF-8 /usr/sbin/sshd -D
env -i LANG=C /usr/sbin/sshd -hNo comments yet.