diff --git a/lib/krb5/krb5.conf.5 b/lib/krb5/krb5.conf.5
index 83e4e602b..8d26e10d1 100644
--- a/lib/krb5/krb5.conf.5
+++ b/lib/krb5/krb5.conf.5
@@ -300,6 +300,8 @@ The time before expiration that the user should be warned that her
 password is about to expire.
 .It logging = Va Logging
 What type of logging the kdc should use, see also [logging]/kdc.
+.It use_2b = Va principal list
+List of principals to use AFS 2b tokens for.
 .El
 .It Li [kadmin]
 .Bl -tag -width "xxx" -offset indent