1. Log in as a user (user 1). Check that user 1's messaging settings are set so that "Personal messages between users" go to email while not online and to a popup window while online.
2. Log user 1 out.
3. Log in as another user (user 2).
4. Send a message from user 2 to user 1.
5. Verify that user 1 receives an email notification of the message.