As for poison, you do not need to right click the weapon on top of the
poison. Simply right-clicking the poison applies it to the weapon in the
primary melee slot. Right clicking a weapon in the secondary slot on top
of the poison still poisons the primary weapon slot. Basically, Verant
threw in the step of right clicking the weapon to make people think they
wrote more code than they actually did :)

>The only thing that works by right-clicking one item over another is rogue
>poisoning, but I don't think you can really use the word 'works' in
>connection with that. But this does tell us that that particular game
>mechanic exists.