CKEditor.

The error came from some script in Application.js

config/application.rb

@@ -25,6 +25,7 @@ module PrototypeR4
     # Custom directories with classes and modules you want to be autoloadable.
     # config.autoload_paths += %W(#{config.root}/extras)
     config.autoload_paths = %W(#{config.root}/lib)
+    config.autoload_paths += %W( #{config.root}/app/models/ckeditor )
 
     # Only load the plugins named here, in the order given (default is alphabetical).
     # :all can be used as a placeholder for all plugins not explicitly named.

config/initializers/ckeditor.rb

@@ -0,0 +1,54 @@
+# Use this hook to configure ckeditor
+if Object.const_defined?("Ckeditor")
+  Ckeditor.setup do |config|
+    # The file_post_name allows you to set the value name used to post the file. 
+    # This is not related to the file name. The default value is 'data'. 
+    # For maximum compatibility it is recommended that the default value is used.
+    #config.swf_file_post_name = "data"
+
+    # A text description that is displayed to the user in the File Browser dialog. 
+    #config.swf_file_types_description = "Files"
+
+    # The file_types setting accepts a semi-colon separated list of file extensions 
+    # that are allowed to be selected by the user. Use '*.*' to allow all file types.
+    #config.swf_file_types = "*.doc;*.wpd;*.pdf;*.swf;*.xls"
+
+    # The file_size_limit setting defines the maximum allowed size of a file to be uploaded. 
+    # This setting accepts a value and unit. Valid units are B, KB, MB and GB. 
+    # If the unit is omitted default is KB. A value of 0 (zero) is interpreted as unlimited.
+    # Note: This setting only applies to the user's browser. It does not affect any settings or limits on the web server. 
+    #config.swf_file_size_limit = "10 MB"
+     
+    # Defines the number of files allowed to be uploaded by SWFUpload. 
+    # This setting also sets the upper bound of the file_queue_limit setting. 
+    # Once the user has uploaded or queued the maximum number of files she will 
+    # no longer be able to queue additional files. The value of 0 (zero) is interpreted as unlimited. 
+    # Only successful uploads (uploads the trigger the uploadSuccess event) are counted toward the upload limit. 
+    # The setStats function can be used to modify the number of successful uploads.
+    # Note: This value is not tracked across pages and is reset when a page is refreshed. 
+    # File quotas should be managed by the web server.
+    #config.swf_file_upload_limit = 5
+     
+    # The same as for downloads files, only to upload images
+    #config.swf_image_file_types_description = "Images"
+    #config.swf_image_file_types = "*.jpg;*.jpeg;*.png;*.gif"
+    #config.swf_image_file_size_limit = "5 MB"
+    #config.swf_image_file_upload_limit = 10
+    
+    # Path for view all uploaded files
+    #config.file_manager_uri = "/ckeditor/attachments"
+    
+    # Path for upload files process
+    #config.file_manager_upload_uri = "/ckeditor/attachments"
+    
+    # Path for view all uploaded images
+    #config.file_manager_image_uri = "/ckeditor/pictures"
+    
+    # Path for upload images process
+    #config.file_manager_image_upload_uri = "/ckeditor/pictures"
+   
+    # Model's names witch processing in ckeditor_controller
+    #config.file_manager_image_model = "Ckeditor::Picture"
+    #config.file_manager_file_model = "Ckeditor::AttachmentFile"
+  end
+end