Getting the actual posters e-mail address from the guestbook

I am using the advanced guestbook, I was not sure on how to explain what is happening so here is the steps:

1. Customer leaves guestbook entry.
2. Customer receives message thanking them for sending the guestbook
entry.
3. Customer gets e-mail thanking them for posting.
3. Guestbook sends an e-mail to me but where the person put their e-
mail address it shows as
person@linhost217.prod.mesa1.secureserver.net>

How do you get the persons actual email address to come through. I am getting a bounce back message each time someone post to my guestbook. I have a auto responder that is actually trying to send out a reply to that particular e-mail address. Can this be changed?