diff --git a/ethcore/res/ethereum/frontier.json b/ethcore/res/ethereum/frontier.json
index a9ed4eb45..c74d15d3a 100644
--- a/ethcore/res/ethereum/frontier.json
+++ b/ethcore/res/ethereum/frontier.json
@@ -131,10 +131,10 @@
 					"0x807640a13483f8ac783c557fcdf27be11ea4ac7a"
 				],
 				"eip150Transition": "0x259518",
-				"eip155Transition": "0x7fffffffffffffff",
-				"eip160Transition": "0x7fffffffffffffff",
-				"eip161abcTransition": "0x7fffffffffffffff",
-				"eip161dTransition": "0x7fffffffffffffff"
+				"eip155Transition": "2675000 ",
+				"eip160Transition": "2675000",
+				"eip161abcTransition": "2675000",
+				"eip161dTransition": "2675000"
 			}
 		}
 	},
diff --git a/ethcore/res/ethereum/morden.json b/ethcore/res/ethereum/morden.json
index 3acc8796a..c74b3dc4d 100644
--- a/ethcore/res/ethereum/morden.json
+++ b/ethcore/res/ethereum/morden.json
@@ -11,10 +11,10 @@
 				"registrar": "0x8e4e9b13d4b45cb0befc93c3061b1408f67316b2",
 				"homesteadTransition": "0x789b0",
 				"eip150Transition": "0x1b34d8",
-				"eip155Transition": "0x7fffffffffffffff",
-				"eip160Transition": "0x7fffffffffffffff",
-				"eip161abcTransition": "0x7fffffffffffffff",
-				"eip161dTransition": "0x7fffffffffffffff"
+				"eip155Transition": "1885000",
+				"eip160Transition": "1885000",
+				"eip161abcTransition": "1885000",
+				"eip161dTransition": "1885000"
 			}
 		}
 	},