Project System 2006 is sending the emails about the new comments associated with the project. If you want to subscribe comments please click the 'Subscribe Comments' button on the 'List of Comments' page of the project. If you subscribe the comments in the project then you will receive the emails which will inform you about new comment in this project. Each time if the users leave the comment you will receive the email containing the complex information about the comment. If you want to unsubscribe comments please click the 'Unsubscribe Comments' button in the 'List of Comments' page of the project.