I've found a few steps helpful when setting up dbmail on openbsd. First off I used a fresh install of OpenBSD 3.7 and used qmail as my mta. This meant that I had to pipe the messages to the database. OpenBSD's default shell does not support the syntax suggested in the INSTALL.qmail file so I have included some different information.
1. Download everything from CVS.
2. Once downloaded follow the instructions to get dbmail compiled and installed.
3. Setup the “Pipe” method:
|/usr/local/sbin/dbmail-smtp -d ${RECIPIENT:8}
DOESN'T WORK! Use this
|/usr/local/sbin/dbmail-smtp -d ${RECIPIENT#????????};
Where there are as many question marks as preceding letters you'd like to remove from the email address. Hope someone finds this helpful.