What is a 3mod weapon?

I've seen this term a couple of times... saw it again today, here. I'm not real clear on what that is...? I'm assuming they're not talking about like an inscribable staff which can have three mods added to it: inscription, head, wrap.

So what do they mean by a 3mod? And why would they be removed from the game?

Thanks

a 3 mod weapon is a (for lack of a better word) "bugged" item that could be found in the Monolithium that Rotscale is guarding.
During Halloween 2010, we could finally enter the area via a holiday quest. It was possible to get items dropped that were non-inscribable that had more mods than they should, such as a shield with +25 health, -2 dmg while in stance, +10 armor vs. slashing.

ANET has said that they plan to have an update to remove/fix these weapons, but have yet to do so.

It is an item that could normally only have 2 mods, like a wand or a shield that suddenly got 3. Like the air wand I got with +5 ene and 10% general HCT and 19% HSR for air spells.
They dropped in that halloween quest, appearently since it combined drops from areas with different kinds of drops. So it was never intended that such items should exist.
They give an unfair advantage over people with regular weapons.
My wand might not do the big difference, but imagine a monk with a similar monk wand in high end pvp, it could make a difference.

Awesome, thanks