# File lib/orm_adapter/adapters/active_record.rb, line 18
    def self.model_classes
      begin
        klasses = ::ActiveRecord::Base.__send__(:descendants) # Rails 3
      rescue
        klasses = ::ActiveRecord::Base.__send__(:subclasses) # Rails 2
      end

      klasses.select do |klass|
        !klass.abstract_class? && !except_classes.include?(klass.name)
      end
    end