Internal messages between users of a ROR3 website: ready components?

Developing a new ROR3 website, I need to implement a sort of internal mail system:

• user1 sends a message t开发者_如何学编程o user2
• user2 receives a real-world email and can also see the message in his "Inbox" on the website.
• user1 sees the message in his "Sent mail" folder.

Many websites have this feature.

Is there a Ruby on Rails module to add this feature with minimal development/maintenance?

Note: Simple messages (title and body, plain text) is good enough

Pretty straight forward to implement on your own.

Create a Message model like this

Message
  fromUserId
  toUserId
  title
  body
  is_read
  created_at

And when a message is created you can just create an email copy that you automatically send to toUserId.