Backbone 0.9.0 "previous" weirdness if you override its "change"

previous.js

var Foo = Backbone.Model.extend({ 
 initialize: function() {
  _.bindAll(this, 'change');
  this.bind('change', this.change);
 },
 change: function() { console.log(this.previous('foo'), "to", this.get('foo')) }
});

var f = new Foo({foo: 1});

f.set({foo: 2})
// 1 "to" 2

f.set({foo: "hi"})
// 1 "to" "hi"

f.set({foo: "33"})
// 1 "to" "33"


// The reason for this is because we're overriding `change` up above!