acts_as_state_machine :initial => :pending
  state :pending
  state :enabled
  state :disabled

  event :enable do
    transitions :from => :pending, :to => :enabled
    transitions :from => :disabled, :to => :enabled
  end

  event :disable do
    transitions :from => :pending, :to => :disabled
    transitions :from => :enabled, :to => :disabled
  end
end

Here, normal user registration will cause initial state of 

user object to be a "pending" state; but when admin creates

 an user it should be "enabled", but asm will force the model 

to keep the state to be "pending".

We can achieve required solution by doing the following:--

def create
  User.write_inheritable_attribute :initial_state, :enabled
  user = User.new(params[:user])
  user.save
end

Cheers