| Count | MTA |
|---|---|
| 571 | blocked |
| 513 | MS Exchange |
| 236 | unknown |
| 209 | postfix |
| 158 | Cisco |
| 120 | barracuda |
| 87 | Exim |
| 38 | mdaemon |
| 38 | MailEnable |
| 21 | mailmarshal |
| 20 | qmail |
| 12 | eSafe |
| 12 | IceWarp |
| 12 | communigate |
| 11 | sendmail |
| 11 | TrendMicro Reputation |
| 9 | Sophos |
| 7 | Lotus Domino |
| 3 | SonicWALL |
| 2 | EMailArchitect |
| 1 | intermail |
| 1 | coremail |
| 1 | mirapoint |
| 1 | modusMail |
| 1 | XMail |
| 1 | Mercury |
| 1 | rblsmtpd |
| 1 | Kerio |
| 1 | Lyris |
| 2099 | TOTAL |