Ashenzari and armour binding

[onryo]

So, I've got this Spriggan Stalker of Ashenzari, with a cursed dagger, a cursed cloak, a cursed robe, and a cursed amulet, but also one uncursed ring. It says "You are bound in weapon but not armour or magic." Why am I not bound in armour? All of the armour I'm wearing is cursed, and I haven't found any armour I can wear aside from cloaks and robes.

[Kate]

You need more than half your available armour slots to be cursed. For a spriggan, that means 3 out of 4 (robe, cloak, cap, shield).