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index 0b1a447b764ce342dc90e7be313989163f7a1658..de131f693e8e00ccc94db84133ec3f510eb0b054 100644
--- a/README
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@@ -1 +1,8 @@
 Nexedi Enterprise Objects
+
+  This implementation is based on the protocol version 2,
+  which is documented in doc/protocol.txt.
+
+  NEO must be rewritten based on the protocol version 3.0,
+  which is being documented in doc/spec.stx. The specification
+  is being worked on, and requires more effort to finish.