When using scim as input method, quite often typing suddenly doesn't work. I'll have to click somewhere else and back there to get to type again. This happens when I'm not using the pinyin input method. This resolves when I change the input method back to none.
$sudo apt-get install scim-qtimm im-switch scim-pinyin
$im-switch -z en_US -s scim
Using Ubuntu 10.04.1 LTS
When using the TopCoder Contest Arena Applet, I can't type in the password in scim mode. I have to click auto-detect first, then cancel, and finally type in the password. This resolves when the input method is changed to none.