diff --git a/ethchain/block.go b/ethchain/block.go
index fc7c6b13fb012184d45f7e2881e192af0473b3e1..951bd8de3bbe71a9310c1b6a163ad9aeb4b05eaf 100644
--- a/ethchain/block.go
+++ b/ethchain/block.go
@@ -130,7 +130,7 @@ func CreateBlock(root interface{},
 		Nonce:       Nonce,
 		Time:        time.Now().Unix(),
 		Extra:       extra,
-		UncleSha:    EmptyShaList, //nil,
+		UncleSha:    nil,
 		GasUsed:     new(big.Int),
 		MinGasPrice: new(big.Int),
 		GasLimit:    new(big.Int),
@@ -237,9 +237,9 @@ func (block *Block) SetUncles(uncles []*Block) {
 	block.Uncles = uncles
 
 	// Sha of the concatenated uncles
-	//if len(uncles) > 0 {
-	//	block.UncleSha = ethcrypto.Sha3(ethutil.Encode(block.rlpUncles()))
-	//}
+	if len(uncles) > 0 {
+		block.UncleSha = ethcrypto.Sha3(ethutil.Encode(block.rlpUncles()))
+	}
 }
 
 func (self *Block) SetReceipts(receipts []*Receipt, txs []*Transaction) {
diff --git a/ethchain/genesis.go b/ethchain/genesis.go
index ab6469bb4dc9c45fdc00ed1fffc24d336342c73c..8a6cb55276b8b223d5f35949675c0aefefa92c77 100644
--- a/ethchain/genesis.go
+++ b/ethchain/genesis.go
@@ -18,9 +18,8 @@ var EmptyShaList = ethcrypto.Sha3(ethutil.Encode([]interface{}{}))
 var GenesisHeader = []interface{}{
 	// Previous hash (none)
 	ZeroHash256,
-	ethcrypto.Sha3(ethutil.Encode([]interface{}{})),
 	// Empty uncles
-	//"",
+	"",
 	// Coinbase
 	ZeroHash160,
 	// Root state