I have the same problem as https://askubuntu.com/q/71177/64152. I am trying to use iBus for Japanese input in kubuntu, but neither the icon nor the candidates box appear.
I have found a few threads online asking about the problem, but they all end unanswered and abandoned :(
Short answer: sudo apt-get install gnome-icon-theme
Longer answer: ibus ui need certain GNOME/GTK icons that is not installed on Kubuntu by default. This is a packaging mistake actually. https://bugs.launchpad.net/ubuntu/+source/ibus/+bug/854333
If you just want to have Japanese input and don't mind a rather "Japanized" system, then using the version compiled by the "ubuntu Japanese Team" would be the easiest way to get what you want. They only provide ubuntu, i.e. no k/l/xubuntu, but even after installing the KDE desktop on top of it, the Japanese input works flawlessly. Looking at the amount of still unsolved problems with ibus and other language input systems on previous (k)ubuntu versions I wouldn't count on a soon available solution for the "normal" (k)ubuntu. As you have seen most questions related to these problems remain either unanswered or get closed because of too little interest for the crowd (aka "too localized").
