From the README file: This package contains testing software configured to work with the DSBL (http://dsbl.org/) or DSBL-compliant services. It enables you to send tests to servers based on spam that you receive. If those tests succeed, the results will reach the DSBL host in question, and the relay will be listed. WWW: http://ares.penguinhosting.net/~ian/ - Dean dean@odyssey.apana.org.au