diff --git a/core/block_processor_test.go b/core/block_processor_test.go
index ad29404e1..64add7e8b 100644
--- a/core/block_processor_test.go
+++ b/core/block_processor_test.go
@@ -4,6 +4,7 @@ import (
 	"math/big"
 	"testing"
 
+	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/pow/ezp"
@@ -19,7 +20,7 @@ func proc() (*BlockProcessor, *ChainManager) {
 
 func TestNumber(t *testing.T) {
 	bp, chain := proc()
-	block1 := chain.NewBlock(nil)
+	block1 := chain.NewBlock(common.Address{})
 	block1.Header().Number = big.NewInt(3)
 
 	err := bp.ValidateHeader(block1.Header(), chain.Genesis().Header())
@@ -27,7 +28,7 @@ func TestNumber(t *testing.T) {
 		t.Errorf("expected block number error")
 	}
 
-	block1 = chain.NewBlock(nil)
+	block1 = chain.NewBlock(common.Address{})
 	err = bp.ValidateHeader(block1.Header(), chain.Genesis().Header())
 	if err == BlockNumberErr {
 		t.Errorf("didn't expect block number error")
diff --git a/core/chain_manager_test.go b/core/chain_manager_test.go
index 898d37f9c..e49e594a3 100644
--- a/core/chain_manager_test.go
+++ b/core/chain_manager_test.go
@@ -1,7 +1,6 @@
 package core
 
 import (
-	"bytes"
 	"fmt"
 	"math/big"
 	"os"
@@ -35,7 +34,7 @@ func testFork(t *testing.T, bman *BlockProcessor, i, N int, f func(td1, td2 *big
 	// asert the bmans have the same block at i
 	bi1 := bman.bc.GetBlockByNumber(uint64(i)).Hash()
 	bi2 := bman2.bc.GetBlockByNumber(uint64(i)).Hash()
-	if bytes.Compare(bi1, bi2) != 0 {
+	if bi1 != bi2 {
 		t.Fatal("chains do not have the same hash at height", i)
 	}
 
@@ -270,11 +269,11 @@ func TestChainInsertions(t *testing.T) {
 		<-done
 	}
 
-	if bytes.Equal(chain2[len(chain2)-1].Hash(), chainMan.CurrentBlock().Hash()) {
+	if chain2[len(chain2)-1].Hash() != chainMan.CurrentBlock().Hash() {
 		t.Error("chain2 is canonical and shouldn't be")
 	}
 
-	if !bytes.Equal(chain1[len(chain1)-1].Hash(), chainMan.CurrentBlock().Hash()) {
+	if chain1[len(chain1)-1].Hash() != chainMan.CurrentBlock().Hash() {
 		t.Error("chain1 isn't canonical and should be")
 	}
 }
@@ -320,7 +319,7 @@ func TestChainMultipleInsertions(t *testing.T) {
 		<-done
 	}
 
-	if !bytes.Equal(chains[longest][len(chains[longest])-1].Hash(), chainMan.CurrentBlock().Hash()) {
+	if chains[longest][len(chains[longest])-1].Hash() != chainMan.CurrentBlock().Hash() {
 		t.Error("Invalid canonical chain")
 	}
 }
diff --git a/core/genesis.go b/core/genesis.go
index 70845b502..3e00533ae 100644
--- a/core/genesis.go
+++ b/core/genesis.go
@@ -8,7 +8,6 @@ import (
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
-	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/state"
 )
 
@@ -19,9 +18,6 @@ import (
 var ZeroHash256 = make([]byte, 32)
 var ZeroHash160 = make([]byte, 20)
 var ZeroHash512 = make([]byte, 64)
-var EmptyShaList = crypto.Sha3(common.Encode([]interface{}{}))
-var EmptyListRoot = crypto.Sha3(common.Encode(""))
-
 var GenesisDiff = big.NewInt(131072)
 var GenesisGasLimit = big.NewInt(3141592)
 
diff --git a/core/transaction_pool.go b/core/transaction_pool.go
index 7c50e5e53..f2fe5c748 100644
--- a/core/transaction_pool.go
+++ b/core/transaction_pool.go
@@ -63,7 +63,7 @@ func NewTxPool(eventMux *event.TypeMux) *TxPool {
 func (pool *TxPool) ValidateTransaction(tx *types.Transaction) error {
 	// Validate sender
 	if _, err := tx.From(); err != nil {
-		return err
+		return ErrInvalidSender
 	}
 	// Validate curve param
 	v, _, _ := tx.Curve()
diff --git a/core/transaction_pool_test.go b/core/transaction_pool_test.go
index 418cb0415..bf9012573 100644
--- a/core/transaction_pool_test.go
+++ b/core/transaction_pool_test.go
@@ -4,10 +4,10 @@ import (
 	"crypto/ecdsa"
 	"testing"
 
+	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/ethdb"
-	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/state"
 )
@@ -21,11 +21,11 @@ func SQ() stateQuery {
 }
 
 func (self stateQuery) GetAccount(addr []byte) *state.StateObject {
-	return state.NewStateObject(addr, self.db)
+	return state.NewStateObject(common.BytesToAddress(addr), self.db)
 }
 
 func transaction() *types.Transaction {
-	return types.NewTransactionMessage(make([]byte, 20), common.Big0, common.Big0, common.Big0, nil)
+	return types.NewTransactionMessage(common.Address{}, common.Big0, common.Big0, common.Big0, nil)
 }
 
 func setup() (*TxPool, *ecdsa.PrivateKey) {
@@ -88,10 +88,8 @@ func TestRemoveInvalid(t *testing.T) {
 
 func TestInvalidSender(t *testing.T) {
 	pool, _ := setup()
-	tx := new(types.Transaction)
-	tx.V = 28
-	err := pool.ValidateTransaction(tx)
+	err := pool.ValidateTransaction(new(types.Transaction))
 	if err != ErrInvalidSender {
-		t.Error("expected %v, got %v", ErrInvalidSender, err)
+		t.Errorf("expected %v, got %v", ErrInvalidSender, err)
 	}
 }