not all input method shows up with update-alternative --config xinput-all_ALL

[mathfeel]

I want to switch on ibus for occational CJK input, but only default shows up:

$ sudo update-alternatives --config xinput-all_ALL

There are 3 alternatives which provide `xinput-all_ALL'.

Selection Alternative
-----------------------------------------------
*+ 1 /etc/X11/xinit/xinput.d/default
2 /etc/X11/xinit/xinput.d/default-xim
3 /etc/X11/xinit/xinput.d/none

If I do this with zh_CN, sure:

$ sudo update-alternatives --config xinput-zh_CN

There are 5 alternatives which provide `xinput-zh_CN'.

Selection Alternative
-----------------------------------------------
*+ 1 /etc/X11/xinit/xinput.d/scim-bridge
2 /etc/X11/xinit/xinput.d/scim
3 /etc/X11/xinit/xinput.d/scim-immodule
4 /etc/X11/xinit/xinput.d/scim-pinyin
5 /etc/X11/xinit/xinput.d/ibus

Press enter to keep the default , or type selection number: ^C

Does this means I have to switch my locale from en_US.utf8 to zh_CN.utf8. I certainly don't want my date format and menu show up in Chinese.