bin/console_sandbox in rails-0.12.1 vs bin/console_sandbox in rails-0.13.0

@@ -1,6 +1 @@
-ActiveRecord::Base.lock_mutex
-ActiveRecord::Base.connection.begin_db_transaction
-at_exit do
-  ActiveRecord::Base.connection.rollback_db_transaction
-  ActiveRecord::Base.unlock_mutex
-end
\ No newline at end of file