I have a client that needed to send email from a program on their server so I whitelisted that server ip address to allow them to send through our server. SM can report on the number of messages sent, but not the MB's. So I've asked for that feature to be included. In the meantime, I've written a little program that can compile that info from the SMTP log files. It's not pretty, but it works for me. If anyone else would like it, let me know and I'll pass it along.