Mail statistics - unrecongnized host destination?


Jul 19, 2006
Here is what my mail statistics show, and I'm worried about one particular entry:

Top 50 sending hosts by message count

10194 63MB local
7524 8707KB
548 18MB
129 3799KB
110 1732KB
109 4450KB

Top 50 local senders by message count

9984 42MB mailnull
101 17MB gme
50 4634KB crawley
30 364KB trevorg

Top 50 host destinations by message count

6934 14MB
3257 180MB local
513 1050KB
397 16MB
81 1414KB
16 33KB

Can anyone explain what exactly these stats are telling me? Does it mean that I am getting a lot of mail FROM and SENDING a lot of mail to through mailnull?

I'm having a hard time understanding these statistics. Sorry for being such a noob but the sheer volume of mail disturbs me.