diff --git a/kdc/kerberos5.c b/kdc/kerberos5.c
index e9a5b79e7..d7662658f 100644
--- a/kdc/kerberos5.c
+++ b/kdc/kerberos5.c
@@ -1544,7 +1544,8 @@ generate_pac(kdc_request_t r, Key *skey)
 krb5_boolean
 _kdc_is_anonymous(krb5_context context, krb5_principal principal)
 {
-    if (principal->name.name_type != KRB5_NT_WELLKNOWN ||
+    if ((principal->name.name_type != KRB5_NT_WELLKNOWN &&
+	 principal->name.name_type != KRB5_NT_UNKNOWN) ||
 	principal->name.name_string.len != 2 ||
 	strcmp(principal->name.name_string.val[0], KRB5_WELLKNOWN_NAME) != 0 ||
 	strcmp(principal->name.name_string.val[1], KRB5_ANON_NAME) != 0)