This allows the user's email to better avoid anti-spam filters.
This agent is implemented in java so that it will run on every platform NetMail will run on, though it does support running on a different server than NMAP as well. After installing a JVM, extract the distribution package to its permanent home. Then edit the config file, setting the domain(s) or user(s) whose e-mail you wish to contain hashcash, and other settings as desired. The agent can be launched with the command "java -jar hashcash.jar".