Basically tweaks Jericho from being a very evil karma companion to a hired karma-neutral one (just like Charon).
I think is a question of tweaking the hiring script and some few dialogs to remove the Karma mention when trying to hiring him (and maybe removing/tweaking the lines he says when the player karma start to be too high).
Why? Because he would be a interesting guy to hire to help you early in game. Charon is too "inaccessible" in Underworld to find (only after helping Three Dog Underworld is really on the "path" of players following the master quest).