diff --git a/fail2ban/server/filter.py b/fail2ban/server/filter.py
index 30268815..30ba2649 100644
--- a/fail2ban/server/filter.py
+++ b/fail2ban/server/filter.py
@@ -430,7 +430,8 @@ class Filter(JailThread):
 				if date is None:
 					logSys.debug("Found a match for %r but no valid date/time "
 								 "found for %r. Please try setting a custom "
-								 "date pattern. If format is complex, please "
+								 "date pattern (see man page jail.conf(5)). "
+								 "If format is complex, please "
 								 "file a detailed issue on"
 								 " https://github.com/fail2ban/fail2ban/issues "
 								 "in order to get support for this format."