rake db:annotate aliases annotate_models. running db:migrate, :reset or :redo will run annotate.

lib/tasks/annotate_old.rake

+namespace :db do
+  
+  desc 'Aliases the old db:annotate task name'
+  task :annotate => :environment do
+    Rake::Task["annotate_models"].execute
+  end
+  
+  task :migrate do
+    Rake::Task["annotate_models"].invoke if Rails.env.development?
+  end
+  
+  # ensures that migrate, reset, redo run annotate.
+  
+  namespace :migrate do
+    [:reset, :redo].each do |t|
+      task t do
+        Rake::Task["annotate_models"].invoke if Rails.env.development?
+      end
+    end
+  end
+end