Nerd tree: enter does not open sub dirs

Question

I installed NERDTree via Pathogen on Mac OSX 10.6.8.

When I vim a dir, I cannot enter into sub dirs with enter key. Furthermore, the dirs look like this:

Answer 1

On Mountain Lion 10.8.2

This worked for me

export LC_CTYPE=en_US.UTF-8
export LC_ALL=en_US.UTF-8