Well, I guess that explains why I never tested such a charm.

I remembered there were no ranged damage charms, but (not actually using any charms) didn't really pay too much attention to the 'lesser' types (I did purchase some charms, primarily strength and dexterity, for possible use later in the game, but never needed them). I must have been thinking of the magic damage bonuses on equipment, and assumed there was a corresponding charm.
In D2:ED I tried Fire Curse once, but it didn't seem to be triggered as much as Poison (though the effect may just not have been as noticeable; I never checked the combat log to see if it was being triggered or resisted). I didn't bother putting more than 1 point into the Life/Mana Leech skills, so didn't see much use for the corresponding enchantments (potions were more than adequate for healing and I rarely required that much mana that I couldn't just wait or use a potion for).