你建议我用什么宝石来实现一个简单的“联系我们”表单?

I am using Ruby on Rails 3.0.9 and I am planning to add a simple "Contact us" form to my application in order to make it possible that a user can contact our team. For that I would like to run validation and "friends" functionalities and (to avoid to implement that myself and) to use a third party software, but...I am using Ruby on Rails 3.0.9 and I am plannin