Our frontend server takes over a locale setting of your terminal for ssh client, Mac OS. "SendEnv" setting of your terminal occur it. Please try the following two ways.
 

Modify on "/etc/ssh_config"

Please comment out "SendEnv" setting by # mark on "/etc/ssh_config" as following.
Make sure that it must be done before connecting to frontend server.

Host *
# SendEnv LANG LC_*

write a locale setting on profile

If you want that ssh server take over a locale setting from your terminal but you want to resolve this problem, please write in bash_profile as following

LC_ALL=en.US UTF=8