Rails - Mar 2006 - please help: "undefined method ''updated?''"

Hi,

after updating to rails1.0 (using the debian package) and following the 
instructions at http://manuals.rubyonrails.com/read/chapter/120 
I always get in my rails application the following error:
"undefined method `updated?'' for #<Device:0xb6c95564>"
when I want to save (create or update) an interface or device-object
(as explanation: devices are servers, which have many interfaces).

Thank you in advance for your help to find my mistake!

Kind Regards
 Peter

My relevant code snippets are:
------------------- models/device.rb ---------------------
class Device < ActiveRecord::Base
  belongs_to :devicetype
  belongs_to :devicemodel
  belongs_to :cabinet
  has_many   :interfaces
  has_and_belongs_to_many :groups
  validates_presence_of     :name, :he
  validates_uniqueness_of   :name
  validates_numericality_of :he
[...]
end

------------------- models/device.rb ---------------------
class Interface < ActiveRecord::Base
  belongs_to :device
  belongs_to :cable
  belongs_to :patchcable
  validates_presence_of     :name, :device_id
[...]
end

I want to add a comment to an existing interface, so here''s the update
method:
------------------- controllers/interfaces_controller.rb ---------------------
[...]
  def update
    @interface = Interface.find(params[:id])
    unless @interface.device.is_writable(@logged_user)
      flash[:error] = ''Keine Berechtigung!''
      redirect_to :action => ''show'', :id =>
@interface.id
    else
      if params[:interface][:upstream] != "1"
        params[:interface][:upstream] = ''''
      end
      if @interface.update_attributes(params[:interface])
        flash[:notice] = ''Schnittstelle wurde aktualisiert.''
        redirect_to :action => ''show'', :id => @interface
      else
        render :action => ''edit''
      end
    end
  end
[...]

An interface object consists of name and comment and has relations to a server 
and a cable (and sometimes to an extra patchcable).

The error message I get is:
NoMethodError in Interfaces#update
undefined method `updated?'' for #<Device:0xb6c95564>
RAILS_ROOT: [...]
(Full Trace, "#{RAILS_ROOT}" removed to get rid of some line
breaks...)

/vendor/rails/activerecord/lib/active_record/base.rb:1498:in
`method_missing''
/vendor/rails/activerecord/lib/active_record/callbacks.rb:341:in
`callback''
/vendor/rails/activerecord/lib/active_record/callbacks.rb:335:in
`callback''
/vendor/rails/activerecord/lib/active_record/callbacks.rb:330:in `each''
/vendor/rails/activerecord/lib/active_record/callbacks.rb:330:in
`callback''
/vendor/rails/activerecord/lib/active_record/callbacks.rb:248:in 
`create_or_update''
/vendor/rails/activerecord/lib/active_record/base.rb:1226:in 
`save_without_validation''
/vendor/rails/activerecord/lib/active_record/validations.rb:698:in 
`save_without_transactions''
/vendor/rails/activerecord/lib/active_record/transactions.rb:126:in
`save''
/vendor/rails/activerecord/lib/active_record/transactions.rb:126:in 
`transaction''
/vendor/rails/activerecord/lib/active_record/transactions.rb:91:in 
`transaction''
/vendor/rails/activerecord/lib/active_record/transactions.rb:118:in 
`transaction''
/vendor/rails/activerecord/lib/active_record/transactions.rb:126:in
`save''
/vendor/rails/activerecord/lib/active_record/base.rb:1267:in 
`update_attributes''
/app/controllers/interfaces_controller.rb:102:in `update''
/vendor/rails/actionpack/lib/action_controller/base.rb:853:in 
`perform_action_without_filters''
/vendor/rails/actionpack/lib/action_controller/filters.rb:332:in 
`perform_action_without_benchmark''
/vendor/rails/actionpack/lib/action_controller/benchmarking.rb:69:in 
`perform_action_without_rescue''
/vendor/rails/actionpack/lib/action_controller/benchmarking.rb:69:in
`measure''
/vendor/rails/actionpack/lib/action_controller/benchmarking.rb:69:in 
`perform_action_without_rescue''
/vendor/rails/actionpack/lib/action_controller/rescue.rb:82:in 
`perform_action''
/vendor/rails/actionpack/lib/action_controller/base.rb:369:in 
`process_without_session_management_support''
/vendor/rails/actionpack/lib/action_controller/session_management.rb:116:in 
`process''
/vendor/rails/railties/lib/dispatcher.rb:38:in `dispatch''
/var/www/ccm-psaenger.ncc.eurodata.de_8080/public/dispatch.cgi:12

Peter S?nger wrote:
> after updating to rails1.0 (using the debian package) and following the 
> instructions at http://manuals.rubyonrails.com/read/chapter/120 
> I always get in my rails application the following error:
> "undefined method `updated?'' for
#<Device:0xb6c95564>"
You may like to contact the author of this message, who
had the same problem:

http://article.gmane.org/gmane.comp.lang.ruby.rails/37392

-- 
We develop, watch us RoR, in numbers too big to ignore.

Hi,

thanks to Marshalls help, I figured out, that my problem was caused by a badly 
chosen name of a variable in the validates method of my interface model.
Originally I called it @device, after renaming it the error was gone.

Thanks
 Peter