diff --git a/lib/krb5/krb5_keyblock.3 b/lib/krb5/krb5_keyblock.3
index cfe12a2de..9df25e7a3 100644
--- a/lib/krb5/krb5_keyblock.3
+++ b/lib/krb5/krb5_keyblock.3
@@ -43,6 +43,7 @@
 .Nm krb5_free_keyblock_contents ,
 .Nm krb5_generate_random_keyblock ,
 .Nm krb5_generate_subkey ,
+.Nm krb5_generate_subkey_extended ,
 .Nm krb5_keyblock_zero ,
 .Nm krb5_random_to_key
 .Nd Kerberos 5 key handling functions.
@@ -89,6 +90,13 @@ Kerberos 5 Library (libkrb5, -lkrb5)
 .Fa "const krb5_keyblock *key"
 .Fa "krb5_keyblock **subkey"
 .Fc
+.Ft krb5_error_code
+.Fo krb5_generate_subkey_extended
+.Fa "krb5_context context"
+.Fa "const krb5_keyblock *key"
+.Fa "krb5_enctype enctype"
+.Fa "krb5_keyblock **subkey"
+.Fc
 .Ft void
 .Fo krb5_keyblock_zero
 .Fa "krb5_keyblock *keyblock"
@@ -153,6 +161,20 @@ of the same type as
 The caller must free the subkey with
 .Fa krb5_free_keyblock .
 .Pp
+.Fn krb5_generate_subkey_extended
+generates a
+.Fa subkey
+of the specified encryption type
+.Fa type .
+If
+.Fa type
+is
+.Dv ETYPE_NULL ,
+of the same type as
+.Fa key .
+The caller must free the subkey with
+.Fa krb5_free_keyblock .
+.Pp
 .Fn krb5_keyblock_zero
 zeros out the keyblock to to make sure no keymaterial is in
 memory.