It should work on Kubuntu and X11, but I remember that the installation and configuration process (or at least the documentation) is a bit lacking. Make sure you also install the ibus-[input method] package. If you don't the ibus preferences still allows you to add a chinese/japanese input method, but it doesn't actually do anything. You might also want to restart your x11 session after that.
In my case, I wanted to keep my configured xkb keyboard layouts + I wanted to be able to use ibus in parallel for CJK.
Ok, there must be a problem with *my* KDE setup: when I try to disable KDE keyboard layouts, KDE does not persist changes to the next session: when I log in next time, KDE keyboard layouts are enabled again and interfere with ibus.