ActiveRecord validation reflection

In my model class I have:
class X < ActiveRecord:Base
validates_length_of :login, :within => 3…40

In my view file I do:
Login (3…40 characters)

Is there a way to query this length information?
Hence, having hard-coded “3…40” in the view is NOT good, as the length
limit may change from model definition. I rather do something like:
Login (<%= find_the_frigging_length_from_model_X
%> characters)