Comment # 6 on bug 869133 from Tristan Miller

My environment variables:

QT_IM_MODULE=ibus
XMODIFIERS=@im=ibus
GTK_IM_MODULE=ibus

I have libreoffice-kde4 installed (and not libreoffice-gtk3) but for some
reason my OOO_FORCE_DESKTOP is set to "gnome" by default.  Changing it to "kde"
has no effect on the dead keys behaviour.  Changing it to "x11" or unsetting it
causes dead keys to stop working altogether.