Note: Based on Michal77's post here.

The default setup of SCIM on Gutsy and Hardy produces some irritating errors including the inability to rename files in Nautilus (Gutsy), inability to type jump to files in Nautilus by typing the first few letters (Hardy), and Firefox 3's URL matching in the location bar lagging by a character (Hardy). There are quite likely others, but these are the ones I have personally experienced.

All of these problems can be fixed by installing scim-bridge and using that instead of xim.

To install scim-bridge on Gutsy:
Code:
sudo apt-get install scim-bridge
To install scim-bridge on Hardy:
Code:
sudo apt-get install scim-bridge-agent scim-bridge-client-gtk scim-bridge-client-qt scim-bridge-client-qt4
Now open the scim config file:
Code:
sudo gedit /etc/X11/xinit/xinput.d/scim
and chage the following lines:
Code:
GTK_IM_MODULE=xim
QT_IM_MODULE=xim
to:
Code:
GTK_IM_MODULE="scim-bridge"
QT_IM_MODULE="scim-bridge"
Restarting SCIM is not sufficient so restart X either by restarting the computer (System->Quit->Restart) or hitting [CTL][ALT][BACKSPACE].

WARNING: [CTL][ALT][BACKSPACE] will immediately log out and restart X. Make sure to save anything important before doing this.