Hexen 1.1, Linux, Vavoom 1.28 from source.
Start new game with ie. fighter, play some time, quicksave, start new game again with ie. mage, quickload. You should have your previous (fighter) game. Well, you're in the place where you left, but you play mage. If you found some weapons as a fighter, you have it, but all the new found weapons are of mage (you can switch between the weapon of mage and the corresponding weapon of fighter - cool!). You use flachettes like a mage. And, unfortunately, the game starts to crash from time to time, and when you finish an episode it crashes to death.
I believe that there's a bug in not fully clearing game state while loading game.
This bug is reproducible. Not tested with save/load other than quick.