item textures on enchanted items sold by villagers

when making a villager sell an enchanted emerald, the texture does not work. it works on the 1.7.2 version ofminecraft. command used to summon villager is

/summon Villager ~ ~1 ~ {Offers:{Recipes:[{maxUses:99999,buy:{id:338,Count:64},sell:{id:minecraft:emerald,Count:4,Damage:1,tag:{ench:[{id:16,lvl:2},{id:21,lvl:1},{id:17,lvl:4}]},display:{Name:Killer}}}]}}