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"updated the ajax_on_rails.textile for rails3"

railties/guides/source/active_record_validations_callbacks.textile

@@ -1162,7 +1162,7 @@ class PictureFile < ActiveRecord::Base
 end
 </ruby>
 
-Note that we needed to instantiate a new +PictureFileCallbacks+ object, since we declared our callback as an instance method. This is particularly useful if the callbacks make use of the state of instantiated object. Often, however, it will make more sense to declare the callbacks as class methods:
+Note that we needed to instantiate a new +PictureFileCallbacks+ object, since we declared our callback as an instance method. This is particularly useful if the callbacks make use of the state of the instantiated object. Often, however, it will make more sense to declare the callbacks as class methods:
 
 <ruby>
 class PictureFileCallbacks