sblack162: How do you poison a weapon?
Make your Poison Weapon skill the active skill, right click the game screen (I usually click on the weapon) A small message will appear "Weapon Poisoned !!!" on screen for a moment. . . =)
See attached image
Edit: The critter you are damaging will be green until the poison wears off of the weapon at which time you will need to re-poison the weapon. You will know when as the critters will no longer turn green when struck. Poison Weapon is unavailable if you don't have a flask of poison in your inventory (green).
After making the Poison Weapon skill active, a green flask will appear in your active skill slot. Once you run out of poison, the "Weapon Poisoned !!! message will no longer appear when you right click. If you try to make the poison weapon skill active by left clicking the skill again . . a dialog appears saying "I don't have any poison with me" Get more poison to use the skill again.
I don't leave it active except to poison the weapon then I go back to lightening, linking skills to F keys makes the swapping of active skills very quick and easy.