Collection sync does not store in localStorage properly

[ionutzp]

collection = new Backbone.Collection()
      collection.reset([{
        curr_id: "xxx", name: "XXX", sign: "XXX", description: "Swiss Franc"
      }, {
        curr_id: "yyy", name: "YYY", sign: "YYY", description: "Swiss Franc"
      }])

      collection.sync('create', collection)