diff --git a/sshd_config b/sshd_config
index 2a9b86be2..370c4c8bc 100644
--- a/sshd_config
+++ b/sshd_config
@@ -42,7 +42,8 @@ PasswordAuthentication yes
 PermitEmptyPasswords no
 
 # Comment to enable s/key passwords or PAM interactive authentication
-# NB. Neither of these are compiled in by default.
+# NB. Neither of these are compiled in by default. Please read the
+# notes in the sshd(8) manpage before enabling this on a PAM system.
 ChallengeResponseAuthentication no
 
 # To change Kerberos options