diff --git a/include/package.mk b/include/package.mk
index 1b69cf25d6..ffab228aae 100644
--- a/include/package.mk
+++ b/include/package.mk
@@ -21,7 +21,7 @@ define Build/DefaultTargets
   ifeq ($(DUMP),)
     ifeq ($(CONFIG_AUTOREBUILD),y)
       _INFO:=
-      ifneq ($$(shell $(SCRIPT_DIR)/timestamp.pl -p $(PKG_BUILD_DIR) .),$(PKG_BUILD_DIR))
+      ifneq ($$(shell $(SCRIPT_DIR)/timestamp.pl -p $(PKG_BUILD_DIR) . $(PKG_FILE_DEPEND)),$(PKG_BUILD_DIR))
         _INFO+=$(subst $(TOPDIR)/,,$(PKG_BUILD_DIR))
         $(PKG_BUILD_DIR)/.prepared: package-clean
       endif
diff --git a/package/base-files/Makefile b/package/base-files/Makefile
index 14917f683b..33e6522e7e 100644
--- a/package/base-files/Makefile
+++ b/package/base-files/Makefile
@@ -13,6 +13,7 @@ PKG_NAME:=base-files
 PKG_RELEASE:=8
 
 PKG_BUILD_DIR:=$(KERNEL_BUILD_DIR)/$(PKG_NAME)
+PKG_FILE_DEPEND:=$(PLATFORM_DIR)
 
 REV:=$(shell LANG=C svn info | awk '/^Revision:/ { print$$2 }' )
 ifeq ($(REV),)
diff --git a/scripts/timestamp.pl b/scripts/timestamp.pl
index a3aa50cb0d..a4c5cae015 100755
--- a/scripts/timestamp.pl
+++ b/scripts/timestamp.pl
@@ -17,9 +17,8 @@ sub get_ts($$) {
 	while (<FIND>) {
 		chomp;
 		my $file = $_;
-		open FILE, "<$file";
-		my @stat = stat FILE;
-		close FILE;
+		next if -l $file;
+		my @stat = stat $file;
 		if ($stat[9] > $ts) {
 			$ts = $stat[9];
 			$fn = $file;