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Makefile

@@ -38,7 +38,7 @@ package:
 	# mkdir -p $(build_dir)/config
 	# cp extra file
 	# update release date
-	sed -i "s/Release Date:.*/Release Date: $current_date/" $vfile
+	sed -i "s/Release Date:.*/Release Date: $(current_date)/" $(vfile)
 	cp -rf $(build_root)/extra/* $(build_dir)
 	# cp web file
 	mkdir -p $(build_dir)/web