Unable to assign Shattering Spite from Atziri's Contempt to weapon set.

When assigning Atziri's Contempt spear to both weapon sets, 2 copies of Spear Stab and Spear Throw are available in the skills menu (one for each weapon set), but only 1 copy of Shattering Spite which cannot be assigned to either weapon set specifically and uses the currently active one.