Comment 3 for bug 522814

These have been clean Karmic and Lucid installations. I set my locale and language settings in the Ubiquity installer, and later in System Settings -> Regional and Language if the locale didn't stick.

From the output of locale;
    $ locale
    LANG=en_US.UTF-8
    LANGUAGE=
    LC_CTYPE="en_US.UTF-8"
    LC_NUMERIC="en_US.UTF-8"
    LC_TIME="en_US.UTF-8"
    LC_COLLATE="en_US.UTF-8"
    LC_MONETARY="en_US.UTF-8"
    LC_MESSAGES="en_US.UTF-8"
    LC_PAPER="en_US.UTF-8"
    LC_NAME="en_US.UTF-8"
    LC_ADDRESS="en_US.UTF-8"
    LC_TELEPHONE="en_US.UTF-8"
    LC_MEASUREMENT="en_US.UTF-8"
    LC_IDENTIFICATION="en_US.UTF-8"
    LC_ALL=

From the output of 'im-switch -l';

    $ sudo im-switch -l
    Your input method setup under en_US locale as below.
    =======================================================
    No private configuration can be defined for root account.
    =======================================================
    The system wide default is pointed by "/etc/alternatives/xinput-all_ALL" .
    xinput-all_ALL - auto mode
     link currently points to default
    default - priority 10
    default-xim - priority 0
    none - priority 0
    uim - priority 0
    uim-systray - priority 0
    uim-toolbar - priority 0
    uim-toolbar-qt - priority 0
    Current `best' version is default.
    =======================================================
    The available input method configuration files are:
    default default-xim ibus ibus-kde lo-gtk none th-gtk th-xim uim uim-systray uim-toolbar uim-toolbar-qt
    =======================================================

Note how my system-wide default is pointed by the xinput-all_ALL alternative, which ibus' source is set up to reject.