Rails gem在执行“rake测试”时使用开发db而不是测试db

I'm using a gem with my rails 3 project, "rails-settings-cached", and when I'm in development mode the gem can access the database without any problem. However, when I run "rake test", a lot of tests fails because "rails-settings-cached" keeps using the development db instead of the testing one.I'm using a gem with my rails 3 project, "rails