diff --git a/ethcore/res/ethereum/classic.json b/ethcore/res/ethereum/classic.json
index 5571e2c2a..b3255f4be 100644
--- a/ethcore/res/ethereum/classic.json
+++ b/ethcore/res/ethereum/classic.json
@@ -4466,7 +4466,7 @@
 			"balance": "0x1",
 			"builtin": {
 				"name": "blake2_f",
-				"activate_at": "0x1f67cf",
+				"activate_at": "0xa03ae7",
 				"pricing": {
 					"blake2_f": {
 						"gas_per_round": 1