Multiple times now, I have had flame weapon/darkfire cast on my weapon [shown here (http://gyazo.com/1e25b25414c2a9c12b51c52d24e979c6.png?1344485926).], and multiple times has it failed on me and not applied the buff. I was told by a player that it did not recognize my spear as a melee weapon.
Now, as it does have acid damage, is this intentional? I would imagine not, but just bringing this up.
Elemental damage does not stack up, so that is intentional if your weapon has some.
Yep. Totally intentional.
Also, no elemental damage should ever add up. If you cast 'Deafening Clang', for example, on a weapon with any elemental damage whether spell or already a weapon trait it will not stack.