Rails 3.1 app using gem spine_rails (0.0.9)

Question

I created rails3.1 app in spine.js using spine_rails (0.0.9) gem and eco gem. I created two spine:scaffold in my rails app to relate has_many, belongs_to relationship. I included hasMany, belongs_to in spine:model.

I don't know how to get id from one spine:scaffold to another spine:scaffold.