softegg writes "My company hosts our own mail server. We have high-speed business connections through Verizon and Comcast. Recently, Verizon and Comcast have been blocking port 25, causing our private mail server to stop functioning. Additionally, a lot of ISPs just started blocking any mail coming from any IP in the address block of cable modems. This caused us to start laundering our mail through a third-party service called DNSExit. Now, McAfee's MAPS anti-spam system tells us they are blocking DNSExit for spam. Essentially, we are finding ourselves increasingly cut off from sending any outgoing mail. What is a small company supposed to do if you want to host your own mail?"