I can confirm this problem afflicted another new Ubuntu installation. In this case, I did a pure Japanese installation, but later switched the user language to English. Japanese input was not accessible. (It also messed up the keyboard settings, which had been set for Japanese 106 before.)
The environment variables mentioned above will work, though I couldn't figure out where the best place to install them was. The fix I'm actually using came from the Fedora Core people. (Fedora Core has the same problem.) mkdir .xinput.d ln -s /etc/X11/xinit/xinput.d/scim ~/.xinput.d/default -- Environment not properly prepared for SCIM https://launchpad.net/bugs/62133 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
