diff --git a/dbus_constants.h b/dbus_constants.h
deleted file mode 100644
index e9b66ab..0000000
--- a/dbus_constants.h
+++ /dev/null
@@ -1,42 +0,0 @@
-//
-// Copyright (C) 2010 The Android Open Source Project
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-//
-
-#ifndef UPDATE_ENGINE_DBUS_CONSTANTS_H_
-#define UPDATE_ENGINE_DBUS_CONSTANTS_H_
-
-// TODO(deymo): Remove this file once all clients use "dbus-constants.h"
-// instead. We need to remove it from the ebuild as well.
-
-namespace chromeos_update_engine {
-
-static const char* const kUpdateEngineServiceName = "org.chromium.UpdateEngine";
-static const char* const kUpdateEngineServicePath =
-    "/org/chromium/UpdateEngine";
-static const char* const kUpdateEngineServiceInterface =
-    "org.chromium.UpdateEngineInterface";
-
-// Generic UpdateEngine D-Bus error.
-static const char* const kUpdateEngineServiceErrorFailed =
-    "org.chromium.UpdateEngine.Error.Failed";
-
-// Flags used in the AttemptUpdateWithFlags() D-Bus method.
-typedef enum {
-  kAttemptUpdateFlagNonInteractive = (1<<0)
-} AttemptUpdateFlags;
-
-}  // namespace chromeos_update_engine
-
-#endif  // UPDATE_ENGINE_DBUS_CONSTANTS_H_
diff --git a/payload_generator/generate_delta_main.cc b/payload_generator/generate_delta_main.cc
index 8a49c16..e122fb9 100644
--- a/payload_generator/generate_delta_main.cc
+++ b/payload_generator/generate_delta_main.cc
@@ -256,6 +256,11 @@
                 "e.g. /path/to/sig:/path/to/next:/path/to/last_sig . Each "
                 "signature will be assigned a client version, starting from "
                 "kSignatureOriginalVersion.");
+  DEFINE_string(metadata_signature_file, "",
+                "Raw signature file with the signature of the metadata hash. "
+                "To pass multiple signatures, use a single argument with a "
+                "colon between paths, "
+                "e.g. /path/to/sig:/path/to/next:/path/to/last_sig .");
   DEFINE_int32(chunk_size, 200 * 1024 * 1024,
                "Payload chunk size (-1 for whole files)");
   DEFINE_uint64(rootfs_partition_size,