diff --git a/ethchain/block.go b/ethchain/block.go
index beb2bc14ca..c6c2c1226c 100644
--- a/ethchain/block.go
+++ b/ethchain/block.go
@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"github.com/ethereum/eth-go/ethutil"
 	"math/big"
+	"strconv"
 	"time"
 )
 
@@ -214,7 +215,12 @@ func (block *Block) SetUncles(uncles []*Block) {
 func (block *Block) SetTransactions(txs []*Transaction) {
 	block.transactions = txs
 
-	block.TxSha = ethutil.Sha3Bin(ethutil.Encode(block.rlpTxs()))
+	trie := ethutil.NewTrie(ethutil.Config.Db, "")
+	for i, tx := range txs {
+		trie.Update(strconv.Itoa(i), string(tx.RlpEncode()))
+	}
+
+	block.TxSha = trie.Root.([]byte)
 }
 
 func (block *Block) Value() *ethutil.Value {
@@ -293,45 +299,10 @@ func NewUncleBlockFromValue(header *ethutil.Value) *Block {
 	return block
 }
 
-func (block *Block) String() string {
-	//return fmt.Sprintf("Block(%x):\nPrevHash:%x\nUncleSha:%x\nCoinbase:%x\nRoot:%x\nTxSha:%x\nDiff:%v\nNonce:%x\nTxs:%d\n", block.Hash(), block.PrevHash, block.UncleSha, block.Coinbase, block.state.trie.Root, block.TxSha, block.Difficulty, block.Time, block.Nonce, len(block.transactions))
-	return fmt.Sprintf(`
-	Block(%x):
-	PrevHash:   %x
-	UncleSha:   %x
-	Coinbase:   %x
-	Root:       %x
-	TxSha:      %x
-	Difficulty: %v
-	Number:     %v
-	MinGas:     %v
-	MaxLimit:   %v
-	GasUsed:    %v
-	Time:       %v
-	Extra:      %v
-	Nonce:      %x
-`,
-		block.Hash(),
-		block.PrevHash,
-		block.UncleSha,
-		block.Coinbase,
-		block.state.trie.Root,
-		block.TxSha,
-		block.Difficulty,
-		block.Number,
-		block.MinGasPrice,
-		block.GasLimit,
-		block.GasUsed,
-		block.Time,
-		block.Extra,
-		block.Nonce)
-}
-
 func (block *Block) GetRoot() interface{} {
 	return block.state.trie.Root
 }
 
-//////////// UNEXPORTED /////////////////
 func (block *Block) header() []interface{} {
 	return []interface{}{
 		// Sha of the previous block
@@ -362,3 +333,36 @@ func (block *Block) header() []interface{} {
 		block.Nonce,
 	}
 }
+
+func (block *Block) String() string {
+	return fmt.Sprintf(`
+	BLOCK(%x):
+	PrevHash:   %x
+	UncleSha:   %x
+	Coinbase:   %x
+	Root:       %x
+	TxSha:      %x
+	Difficulty: %v
+	Number:     %v
+	MinGas:     %v
+	MaxLimit:   %v
+	GasUsed:    %v
+	Time:       %v
+	Extra:      %v
+	Nonce:      %x
+`,
+		block.Hash(),
+		block.PrevHash,
+		block.UncleSha,
+		block.Coinbase,
+		block.state.trie.Root,
+		block.TxSha,
+		block.Difficulty,
+		block.Number,
+		block.MinGasPrice,
+		block.GasLimit,
+		block.GasUsed,
+		block.Time,
+		block.Extra,
+		block.Nonce)
+}
diff --git a/ethchain/block_chain.go b/ethchain/block_chain.go
index eb25bd3f40..2865336fbc 100644
--- a/ethchain/block_chain.go
+++ b/ethchain/block_chain.go
@@ -70,6 +70,22 @@ func (bc *BlockChain) NewBlock(coinbase []byte, txs []*Transaction) *Block {
 		diff.Mul(diff, mul)
 		diff.Add(diff, bc.CurrentBlock.Difficulty)
 		block.Difficulty = diff
+
+		block.Number = new(big.Int).Add(bc.CurrentBlock.Number, ethutil.Big1)
+
+		// max(10000, (parent gas limit * (1024 - 1) + (parent gas used * 6 / 5)) / 1024)
+		base := new(big.Int)
+		base2 := new(big.Int)
+		parentGL := bc.CurrentBlock.GasLimit
+		parentUsed := bc.CurrentBlock.GasUsed
+
+		base.Mul(parentGL, big.NewInt(1024-1))
+		base2.Mul(parentUsed, big.NewInt(6))
+		base2.Div(base2, big.NewInt(5))
+		base.Add(base, base2)
+		base.Div(base, big.NewInt(1024))
+
+		block.GasLimit = ethutil.BigMax(big.NewInt(10000), base)
 	}
 
 	return block
diff --git a/ethchain/genesis.go b/ethchain/genesis.go
index 7e145ef533..b8f9f865a3 100644
--- a/ethchain/genesis.go
+++ b/ethchain/genesis.go
@@ -22,9 +22,8 @@ var GenesisHeader = []interface{}{
 	ZeroHash160,
 	// Root state
 	"",
-	//EmptyShaList,
+	// tx sha
 	ZeroHash256,
-	//ethutil.Sha3Bin(ethutil.Encode(ZeroHash256)),
 	// Difficulty
 	ethutil.BigPow(2, 22),
 	// Number