General Black/White List DNSBL Status
 
  General Settings
Advanced

Enable DNS Black List (DNSBL) Checking
DNSBL Spam Tag  (Optional)

  Query Timeout Setting

Actions when Query Timeout
  SMTP
  POP3
Timeout Value  (1-10 Seconds)
Timeout Tag  (Optional)

  DNSBL Domain List

# DNSBL Domain
 
Note:
Each mail relay and sender IP in mail header (under max. number) will be checked against the DNSBL domain servers listed and enabled above.