Exotic one-handed - the same approximately as Bastard Swords. i.e. Simple for humans weilding halflings with two hands, Exotic if the use one.
In general, humanoid one size smaller requires two hands (simple), or exotic.
Humanoid two sizes smaller is one-handed.
Humanoid three sizes smaller is light.
Humanoid of equal size is two-handed exotic.
Quadrupeds count as one size larger.
Range increment is 5'.