Splocker is not an end-user tool. It is designed
for use by Internet Service Providers (ISPs) and people
who have their own Unix-based servers or Virtual Private
Servers.
Splocker is a challenge-response type SPAM blocking tool.
If you are an end-user and would like Splocker for your
email, contact your email provider and ask them to get
Splocker for you.
Splocker source code is available for FREE to ISPs and
other service providers that use Sendmail.
For more details, click here.