Stats about emails sent and received

I have a problem in my server I have multiple clients and I have no way to check if some is sending spam.
I think CWP should implement some way to check some basic stats about emails, total number os emails sent, total number os emails received, the same for for account or better for email.

Any one knows how can I find this kind of information?

Sometime ago one of my clients set a autoresponder in an email then that email start receiving lots and lots of spam an reply to each spam email with an email, it was hard to find the problem because I don't have any way to see the numbers of emails sent by each account.
Some times a website can be hacked and start sending spam from random emails there are any way to find it?