In my /var/log/messages I have a lot (6000+) of:

Jul 16 12:51:20 sole sshd[6669]: Invalid user clamav from 72.3.243.92
Jul 16 12:51:21 sole sshd[6671]: Invalid user appserver from 72.3.243.92
Jul 16 12:51:23 sole sshd[6673]: Invalid user mailman from 72.3.243.92
Jul 16 12:51:25 sole sshd[6675]: Invalid user cyrusimap from 72.3.243.92
Jul 16 12:51:27 sole sshd[6677]: Invalid user qtss from 72.3.243.92
Jul 16 12:51:28 sole sshd[6679]: Invalid user eppc from 72.3.243.92
Jul 16 12:51:30 sole sshd[6681]: Invalid user telnetd from 72.3.243.92
Jul 16 12:51:32 sole sshd[6683]: Invalid user identd from 72.3.243.92
Jul 16 12:51:33 sole sshd[6685]: Invalid user gnats from 72.3.243.92
Jul 16 12:51:35 sole sshd[6687]: Invalid user jeff from 72.3.243.92
Jul 16 12:51:37 sole sshd[6689]: Invalid user irc from 72.3.243.92

what is it? I need to write to something like abuse@72.3.243.92 ?