rails state_machine with after_create callback and validation on_update

Question

I am using the state_machine gem in a model Event.

The initial state of an event is pending.

When I create an event I would like to run an after_create callback to see if I can make the first transition depending on the attributes of the event.

The event model also has a validation that checks if certain attributes did not change.

Now my Problem is, that when the state_machine event :verify gets called in the after_create callback all values are marked as changed from nil to "initial value" and the transition cannot be made due to the fact that the mentioned validation fails.

Now, I really do not understand how this is even possible. How can event.changes return nil => "initial values" for all values if it is an after_create callback? To me it seems that the after_create callback is called before the event was saved the first time. I would expect it to be saved once then make the callback and then only the state attribute should have changed when I call changes before I try to save my event after calling the verifiy event.

Some example code:

class Event < ActiveRecord::Base

  state_machine :initial => :pending do
    ...
    state :pending
    state :verified
    ...
    event :verify do
      transition :pending => :verified
    end
  end

  ...

  validate :validate_some_attributes_did_not_change, :on => :update

  after_create :initial_verification_check

  ...

  private

  def initial_verification_check
    verify! if everything_fine?
  end

  ...

end