DataMapper / State_Machine save hook issue

gistfile1.rb

require 'dm-core'
require 'state_machine'

class Vehicle
  include DataMapper::Resource

  state_machine :initial => :parked do
    event :ignite do
      transition :parked => :idling
    end
  end

  after :save do
    ignite
  end
end

DataMapper.setup(:default, :adapter => :in_memory)

v = Vehicle.new
v.save
p "State after saving is #{v.state}"
v.save
p "State after saving again is #{v.state}"