diff --git a/rakelib/artifacts.rake b/rakelib/artifacts.rake
index e7b519e8a4e..619a97325d0 100644
--- a/rakelib/artifacts.rake
+++ b/rakelib/artifacts.rake
@@ -669,7 +669,7 @@ namespace "artifact" do
       elsif stat.symlink?
         tar.symlink(path_in_tar, File.readlink(path), :mode => stat.mode)
       else
-        tar.add_file_simple(path_in_tar, :mode => stat.mode, :size => stat.size) do |io|
+        tar.add_file_simple(path_in_tar, :mode => stat.mode, :size => stat.size, :mtime => (stat.mtime || Time.now).to_i) do |io|
           File.open(path, 'rb') do |fd|
             chunk = nil
             size = 0