I didnt check the bandwidth, but their mail server is literally being swamped by email.... It is dual xeon processor machine and it nearly cant handle all of the mail going through...
doesn't surprise me. Until i set my mail server to drop any/all invalid emails (as opposed to sending them to "blackhole" which was supposed to drop them correctly, but ended up sending them to root@) my hosting usage was at 2.5-3.5gig/month, my limit was 3gig/month!! i set it to just drop invalid email as opposed to how the guide said to set it up and usage dropped to 450-800meg/month.
Then there's some of the dumb shit that happens on OUR customer net links, some people are just dangerous to everyone else.