diff --git a/expand_date b/expand_date
new file mode 100755
index 0000000..e521b15
--- /dev/null
+++ b/expand_date
@@ -0,0 +1,4 @@
+#! /usr/bin/env ruby
+data = STDIN.read
+last_date = `git log --pretty=format:"%ad" -1`
+puts data.gsub('$Date$', '$Date: ' + last_date.to_s + '$')