if you have rpm/deb or other package of scim 1.2.x and 1.4.0, then it is very simple, just remove the other package if you want test one of them
remind you: you have to remove all scim-* (including skim) associated with that removed version and install the versions compiled against the other scim.
Yes, thank you, I have simpler solution - Arch's pacman, so that isn't a problem Though I still prefer the way of Evolution development but if that will give developers more burden, just ignore me.
Thanks again.