sequelize attribute problem

example.coffee

Sequelize = require 'sequelize'
sequelize = new Sequelize 'sequelize-test', 'postgres', 'changeme123',
    host: 'localhost'
    port: 5432
    dialect: 'postgres'

A = sequelize.define 'a', name: Sequelize.STRING
Attribute = sequelize.define 'attribute', name: Sequelize.STRING

A.hasMany Attribute

sequelize.sync().success ->
    A.create(name: 'a').error (err) ->
        console.log err