During this mission somewhere near the end, Harriet at some point had her weapon unequipped (In the log, I think it's at the point where it says "Harriet Glaive has 4 attacks total"),
And when I re-equipped her javelins, they now had a range of 6, and her spear had a range of 4. I'm not sure what caused this, but it seems like the game registered that she still had the range of her spear after it got de-equipped, and when she put on the javelins, it gave the base 4 range on top of the 2 she still had somehow.
I'm not sure what caused this, as nothing extraordinary happened between when she last attacked an enemy (roughly 7 or 8 turns prior to this), and when I noticed this.
I've never seen this happen before, so not sure how or why this occured.
Image of her extra range:
http://imgur.com/txABExoEdit: Also, un-equipping her spear, then re-equipping it, still has her have 4 range with it, and 6 with javelins when un-and-re-equipped again