Japanese cant be input/displayed on konsole.
Why didn't you guys start testing this months ago?
Konsole with Japanese is hopeless for now. Doesn't work, and no patch exists.
Japanese use kterm if they use KDE.
When Japanese can be input and displayed on konsole?
When someone implements it (volunteers?) - since I don't speak Japanese and
don't have the slightest clue about how to do this, I won't do it myself.
Maybe someone at bugs.kde.org can help.
Partially, it resolved with this patch:
I've already reported that problem on KDE/BTS but I've not got answer at all.
s/it/it\ can\ be/
*** Bug 50560 has been marked as a duplicate of this bug. ***
The kde.gr.jp patch breaks support for all non-Japanese languages.