I'm not sure what's causing it, but my half-drow fighter, 8th level, has the Weapon Focus and Greater Weapon Focus feats for Warhammers. This should be a cumulative +2 to attack rolls. However, when I equip a warhammer, my attack bonus goes from +12 to +13... meaning it either isn't working, or not stacking. Which, is weird, because it was working just fine last week.