bug#11511: Input method of emacs

[theceason]

maybe i should provide more information 

in some case the xim failure to work

the ime tigger C-<SPC>  will still remain the set mark function
if we unset it then C-<SPC> will be not defined 
however the ime is work fine with other gtk apps with the tigger c-<SPC>
when you try ibus without ibus.el 
i believe you will encounter this problem

i think since emacs already port to gtk
why not give it a gtk im interface the solve the long term problem 

here is a bug report in 2005
https://lists.ubuntu.com/archives/ubuntu-users/2005-April/028398.html