You need install all packages with scim-bradge and all with language-selector (in Synaptic).
Them change entry in scim setup:
sudo gedit /etc/X11/xinit/xinput.d/scim
for more details or KDE users check:https://help.ubuntu.com/community/SCIM
if scim will not show-up start it manually in terminal:
I've tested it in Ubuntu 7.04 7.10 and in Mint 5.0.