I got it working, but it was a little different than Mandriva and took a few tries to get working right. I found THIS link, which really cleared up some confusion I had with a few other HOWTO guides I looked at. I applied these tips, but only installed Japanese language support.
One thing to keep in mind is that the file /etc/X11/Xsession.d/74custom-scim_startup doesn’t exist, so you’ll have to make it. I also made a .fonts.conf file in my home directory and restarted X, but deleted it because my fonts went to crap. After I deleted the file, my fonts went back to normal.
After you are done, restart X. You can either make a startup script for scim or skim in the .kde/Autostart directory, or just use the “Run Command…” tool from the menu and run skim or scim (I prefer skim).
Also, the changes are system-wide, so the scim or skim tool will be present on all logins.