diff --git a/ares/CVS-INFO b/ares/CVS-INFO
new file mode 100644
index 0000000000000000000000000000000000000000..7d48d08e42cb9a55c800de49d9b38420e370a662
--- /dev/null
+++ b/ares/CVS-INFO
@@ -0,0 +1,7 @@
+
+CVS-INFO
+
+This file is only present in the CVS - never in release archives. It is used
+as a sentinel file in buildconf.bat in order to differentiate a CVS checkout
+from release and daily snapshot archives.
+