How to set back-end language per user?

Question

I would like to use the english interface for the back-end but I would like to set it to native language for an editor. I know WPML has this feature, but I don't want to install the unsupported WPML just for this reason.

What I am looking is a tiny plugin which gives a switchbox for the user profile page for setting the back-end language. Is there such a plugin?