smf-zombie

If you find messages similar to the following in your maillog

Dec 5 14:03:41 mxxx sm-mta-in[87531]: lB5J3D9u087531:
h-65-166-127-26.sfldn.covad.net [65.166.127.26] did not issue MAIL/
EXPN/VRFY/ETRN during connection to IPv4

they can be very hard to track down as there is no additional
information in either the maillog or the zombie-spam.log.

They are caused by the smf-zombie milter. Addresses can be
whitelisted in the header file (smf-config.h) as:
#define WHITE_LIST "(^127\\.0\\.0\\.1$||^65\\.166\\.127\\.26|^192\\.
168\\.[0-9]+\\.[0-9]+$)"
then make install and restart your mailserver