diff --git a/accounts/abi/bind/auth.go b/accounts/abi/bind/auth.go
index a20852fca..dbb235c14 100644
--- a/accounts/abi/bind/auth.go
+++ b/accounts/abi/bind/auth.go
@@ -52,7 +52,7 @@ func NewKeyedTransactor(key *ecdsa.PrivateKey) *TransactOpts {
 			if address != keyAddr {
 				return nil, errors.New("not authorized to sign this account")
 			}
-			signature, err := crypto.SignEthereum(signer.Hash(tx).Bytes(), key)
+			signature, err := crypto.Sign(signer.Hash(tx).Bytes(), key)
 			if err != nil {
 				return nil, err
 			}
diff --git a/accounts/account_manager.go b/accounts/account_manager.go
index abe442388..12ff30bca 100644
--- a/accounts/account_manager.go
+++ b/accounts/account_manager.go
@@ -136,13 +136,12 @@ func (am *Manager) DeleteAccount(a Account, passphrase string) error {
 	return err
 }
 
-// Sign calculates a ECDSA signature for the given hash.
-// Note, Ethereum signatures have a particular format as described in the
-// yellow paper. Use the SignEthereum function to calculate a signature
-// in Ethereum format.
+// Sign calculates a ECDSA signature for the given hash. The produced signature
+// is in the [R || S || V] format where V is 0 or 1.
 func (am *Manager) Sign(addr common.Address, hash []byte) ([]byte, error) {
 	am.mu.RLock()
 	defer am.mu.RUnlock()
+
 	unlockedKey, found := am.unlocked[addr]
 	if !found {
 		return nil, ErrLocked
@@ -150,28 +149,16 @@ func (am *Manager) Sign(addr common.Address, hash []byte) ([]byte, error) {
 	return crypto.Sign(hash, unlockedKey.PrivateKey)
 }
 
-// SignEthereum calculates a ECDSA signature for the given hash.
-// The signature has the format as described in the Ethereum yellow paper.
-func (am *Manager) SignEthereum(addr common.Address, hash []byte) ([]byte, error) {
-	am.mu.RLock()
-	defer am.mu.RUnlock()
-	unlockedKey, found := am.unlocked[addr]
-	if !found {
-		return nil, ErrLocked
-	}
-	return crypto.SignEthereum(hash, unlockedKey.PrivateKey)
-}
-
-// SignWithPassphrase signs hash if the private key matching the given
-// address can be decrypted with the given passphrase.
+// SignWithPassphrase signs hash if the private key matching the given address
+// can be decrypted with the given passphrase. The produced signature is in the
+// [R || S || V] format where V is 0 or 1.
 func (am *Manager) SignWithPassphrase(addr common.Address, passphrase string, hash []byte) (signature []byte, err error) {
 	_, key, err := am.getDecryptedKey(Account{Address: addr}, passphrase)
 	if err != nil {
 		return nil, err
 	}
-
 	defer zeroKey(key.PrivateKey)
-	return crypto.SignEthereum(hash, key.PrivateKey)
+	return crypto.Sign(hash, key.PrivateKey)
 }
 
 // Unlock unlocks the given account indefinitely.
diff --git a/core/types/block_test.go b/core/types/block_test.go
index b95bddcfc..93435ca00 100644
--- a/core/types/block_test.go
+++ b/core/types/block_test.go
@@ -53,7 +53,7 @@ func TestBlockEncoding(t *testing.T) {
 
 	tx1 := NewTransaction(0, common.HexToAddress("095e7baea6a6c7c4c2dfeb977efac326af552d87"), big.NewInt(10), big.NewInt(50000), big.NewInt(10), nil)
 
-	tx1, _ = tx1.WithSignature(HomesteadSigner{}, common.Hex2Bytes("9bea4c4daac7c7c52e093e6a4c35dbbcf8856f1af7b059ba20253e70848d094f8a8fae537ce25ed8cb5af9adac3f141af69bd515bd2ba031522df09b97dd72b11b"))
+	tx1, _ = tx1.WithSignature(HomesteadSigner{}, common.Hex2Bytes("9bea4c4daac7c7c52e093e6a4c35dbbcf8856f1af7b059ba20253e70848d094f8a8fae537ce25ed8cb5af9adac3f141af69bd515bd2ba031522df09b97dd72b100"))
 	fmt.Println(block.Transactions()[0].Hash())
 	fmt.Println(tx1.data)
 	fmt.Println(tx1.Hash())
diff --git a/core/types/transaction.go b/core/types/transaction.go
index f566dc365..87b54ab30 100644
--- a/core/types/transaction.go
+++ b/core/types/transaction.go
@@ -199,9 +199,9 @@ func (tx *Transaction) UnmarshalJSON(input []byte) error {
 
 	var V byte
 	if isProtectedV((*big.Int)(dec.V)) {
-		V = normaliseV(NewEIP155Signer(deriveChainId((*big.Int)(dec.V))), (*big.Int)(dec.V))
+		V = byte((new(big.Int).Sub((*big.Int)(dec.V), deriveChainId((*big.Int)(dec.V))).Uint64()) - 35)
 	} else {
-		V = byte(((*big.Int)(dec.V)).Uint64())
+		V = byte(((*big.Int)(dec.V)).Uint64() - 27)
 	}
 	if !crypto.ValidateSignatureValues(V, (*big.Int)(dec.R), (*big.Int)(dec.S), false) {
 		return ErrInvalidSig
@@ -272,51 +272,6 @@ func (tx *Transaction) Size() common.StorageSize {
 	return common.StorageSize(c)
 }
 
-/*
-// From returns the address derived from the signature (V, R, S) using secp256k1
-// elliptic curve and an error if it failed deriving or upon an incorrect
-// signature.
-//
-// From Uses the homestead consensus rules to determine whether the signature is
-// valid.
-//
-// From caches the address, allowing it to be used regardless of
-// Frontier / Homestead. however, the first time called it runs
-// signature validations, so we need two versions. This makes it
-// easier to ensure backwards compatibility of things like package rpc
-// where eth_getblockbynumber uses tx.From() and needs to work for
-// both txs before and after the first homestead block. Signatures
-// valid in homestead are a subset of valid ones in Frontier)
-func (tx *Transaction) From() (common.Address, error) {
-	if tx.signer == nil {
-		return common.Address{}, errNoSigner
-	}
-
-	if from := tx.from.Load(); from != nil {
-		return from.(common.Address), nil
-	}
-
-	pubkey, err := tx.signer.PublicKey(tx)
-	if err != nil {
-		return common.Address{}, err
-	}
-	var addr common.Address
-	copy(addr[:], crypto.Keccak256(pubkey[1:])[12:])
-	tx.from.Store(addr)
-	return addr, nil
-}
-
-// SignatureValues returns the ECDSA signature values contained in the transaction.
-func (tx *Transaction) SignatureValues() (v byte, r *big.Int, s *big.Int, err error) {
-	if tx.signer == nil {
-		return 0, nil, nil,errNoSigner
-	}
-
-	return normaliseV(tx.signer, tx.data.V), new(big.Int).Set(tx.data.R),new(big.Int).Set(tx.data.S), nil
-}
-
-*/
-
 // AsMessage returns the transaction as a core.Message.
 //
 // AsMessage requires a signer to derive the sender.
diff --git a/core/types/transaction_signing.go b/core/types/transaction_signing.go
index 7d571643f..8952bd574 100644
--- a/core/types/transaction_signing.go
+++ b/core/types/transaction_signing.go
@@ -53,7 +53,7 @@ func MakeSigner(config *params.ChainConfig, blockNumber *big.Int) Signer {
 // SignECDSA signs the transaction using the given signer and private key
 func SignECDSA(s Signer, tx *Transaction, prv *ecdsa.PrivateKey) (*Transaction, error) {
 	h := s.Hash(tx)
-	sig, err := crypto.SignEthereum(h[:], prv)
+	sig, err := crypto.Sign(h[:], prv)
 	if err != nil {
 		return nil, err
 	}
@@ -91,11 +91,6 @@ func Sender(signer Signer, tx *Transaction) (common.Address, error) {
 	return addr, nil
 }
 
-// SignatureValues returns the ECDSA signature values contained in the transaction.
-func SignatureValues(signer Signer, tx *Transaction) (v byte, r *big.Int, s *big.Int) {
-	return normaliseV(signer, tx.data.V), new(big.Int).Set(tx.data.R), new(big.Int).Set(tx.data.S)
-}
-
 type Signer interface {
 	// Hash returns the rlp encoded hash for signatures
 	Hash(tx *Transaction) common.Hash
@@ -143,17 +138,16 @@ func (s EIP155Signer) PublicKey(tx *Transaction) ([]byte, error) {
 		return nil, ErrInvalidChainId
 	}
 
-	V := normaliseV(s, tx.data.V)
+	V := byte(new(big.Int).Sub(tx.data.V, s.chainIdMul).Uint64() - 35)
 	if !crypto.ValidateSignatureValues(V, tx.data.R, tx.data.S, true) {
 		return nil, ErrInvalidSig
 	}
-
 	// encode the signature in uncompressed format
 	R, S := tx.data.R.Bytes(), tx.data.S.Bytes()
 	sig := make([]byte, 65)
 	copy(sig[32-len(R):32], R)
 	copy(sig[64-len(S):64], S)
-	sig[64] = V - 27
+	sig[64] = V
 
 	// recover the public key from the signature
 	hash := s.Hash(tx)
@@ -167,8 +161,8 @@ func (s EIP155Signer) PublicKey(tx *Transaction) ([]byte, error) {
 	return pub, nil
 }
 
-// WithSignature returns a new transaction with the given signature.
-// This signature needs to be formatted as described in the yellow paper (v+27).
+// WithSignature returns a new transaction with the given signature. This signature
+// needs to be in the [R || S || V] format where V is 0 or 1.
 func (s EIP155Signer) WithSignature(tx *Transaction, sig []byte) (*Transaction, error) {
 	if len(sig) != 65 {
 		panic(fmt.Sprintf("wrong size for snature: got %d, want 65", len(sig)))
@@ -179,7 +173,7 @@ func (s EIP155Signer) WithSignature(tx *Transaction, sig []byte) (*Transaction,
 	cpy.data.S = new(big.Int).SetBytes(sig[32:64])
 	cpy.data.V = new(big.Int).SetBytes([]byte{sig[64]})
 	if s.chainId.BitLen() > 0 {
-		cpy.data.V = big.NewInt(int64(sig[64] - 27 + 35))
+		cpy.data.V = big.NewInt(int64(sig[64] + 35))
 		cpy.data.V.Add(cpy.data.V, s.chainIdMul)
 	}
 	return cpy, nil
@@ -201,7 +195,7 @@ func (s EIP155Signer) Hash(tx *Transaction) common.Hash {
 
 func (s EIP155Signer) SigECDSA(tx *Transaction, prv *ecdsa.PrivateKey) (*Transaction, error) {
 	h := s.Hash(tx)
-	sig, err := crypto.SignEthereum(h[:], prv)
+	sig, err := crypto.Sign(h[:], prv)
 	if err != nil {
 		return nil, err
 	}
@@ -217,8 +211,8 @@ func (s HomesteadSigner) Equal(s2 Signer) bool {
 	return ok
 }
 
-// WithSignature returns a new transaction with the given snature.
-// This snature needs to be formatted as described in the yellow paper (v+27).
+// WithSignature returns a new transaction with the given signature. This signature
+// needs to be in the [R || S || V] format where V is 0 or 1.
 func (hs HomesteadSigner) WithSignature(tx *Transaction, sig []byte) (*Transaction, error) {
 	if len(sig) != 65 {
 		panic(fmt.Sprintf("wrong size for snature: got %d, want 65", len(sig)))
@@ -226,13 +220,13 @@ func (hs HomesteadSigner) WithSignature(tx *Transaction, sig []byte) (*Transacti
 	cpy := &Transaction{data: tx.data}
 	cpy.data.R = new(big.Int).SetBytes(sig[:32])
 	cpy.data.S = new(big.Int).SetBytes(sig[32:64])
-	cpy.data.V = new(big.Int).SetBytes([]byte{sig[64]})
+	cpy.data.V = new(big.Int).SetBytes([]byte{sig[64] + 27})
 	return cpy, nil
 }
 
 func (hs HomesteadSigner) SignECDSA(tx *Transaction, prv *ecdsa.PrivateKey) (*Transaction, error) {
 	h := hs.Hash(tx)
-	sig, err := crypto.SignEthereum(h[:], prv)
+	sig, err := crypto.Sign(h[:], prv)
 	if err != nil {
 		return nil, err
 	}
@@ -243,7 +237,7 @@ func (hs HomesteadSigner) PublicKey(tx *Transaction) ([]byte, error) {
 	if tx.data.V.BitLen() > 8 {
 		return nil, ErrInvalidSig
 	}
-	V := byte(tx.data.V.Uint64())
+	V := byte(tx.data.V.Uint64() - 27)
 	if !crypto.ValidateSignatureValues(V, tx.data.R, tx.data.S, true) {
 		return nil, ErrInvalidSig
 	}
@@ -252,7 +246,7 @@ func (hs HomesteadSigner) PublicKey(tx *Transaction) ([]byte, error) {
 	sig := make([]byte, 65)
 	copy(sig[32-len(r):32], r)
 	copy(sig[64-len(s):64], s)
-	sig[64] = V - 27
+	sig[64] = V
 
 	// recover the public key from the snature
 	hash := hs.Hash(tx)
@@ -273,8 +267,8 @@ func (s FrontierSigner) Equal(s2 Signer) bool {
 	return ok
 }
 
-// WithSignature returns a new transaction with the given snature.
-// This snature needs to be formatted as described in the yellow paper (v+27).
+// WithSignature returns a new transaction with the given signature. This signature
+// needs to be in the [R || S || V] format where V is 0 or 1.
 func (fs FrontierSigner) WithSignature(tx *Transaction, sig []byte) (*Transaction, error) {
 	if len(sig) != 65 {
 		panic(fmt.Sprintf("wrong size for snature: got %d, want 65", len(sig)))
@@ -282,13 +276,13 @@ func (fs FrontierSigner) WithSignature(tx *Transaction, sig []byte) (*Transactio
 	cpy := &Transaction{data: tx.data}
 	cpy.data.R = new(big.Int).SetBytes(sig[:32])
 	cpy.data.S = new(big.Int).SetBytes(sig[32:64])
-	cpy.data.V = new(big.Int).SetBytes([]byte{sig[64]})
+	cpy.data.V = new(big.Int).SetBytes([]byte{sig[64] + 27})
 	return cpy, nil
 }
 
 func (fs FrontierSigner) SignECDSA(tx *Transaction, prv *ecdsa.PrivateKey) (*Transaction, error) {
 	h := fs.Hash(tx)
-	sig, err := crypto.SignEthereum(h[:], prv)
+	sig, err := crypto.Sign(h[:], prv)
 	if err != nil {
 		return nil, err
 	}
@@ -313,7 +307,7 @@ func (fs FrontierSigner) PublicKey(tx *Transaction) ([]byte, error) {
 		return nil, ErrInvalidSig
 	}
 
-	V := byte(tx.data.V.Uint64())
+	V := byte(tx.data.V.Uint64() - 27)
 	if !crypto.ValidateSignatureValues(V, tx.data.R, tx.data.S, false) {
 		return nil, ErrInvalidSig
 	}
@@ -322,7 +316,7 @@ func (fs FrontierSigner) PublicKey(tx *Transaction) ([]byte, error) {
 	sig := make([]byte, 65)
 	copy(sig[32-len(r):32], r)
 	copy(sig[64-len(s):64], s)
-	sig[64] = V - 27
+	sig[64] = V
 
 	// recover the public key from the snature
 	hash := fs.Hash(tx)
@@ -336,18 +330,6 @@ func (fs FrontierSigner) PublicKey(tx *Transaction) ([]byte, error) {
 	return pub, nil
 }
 
-// normaliseV returns the Ethereum version of the V parameter
-func normaliseV(s Signer, v *big.Int) byte {
-	if s, ok := s.(EIP155Signer); ok {
-		stdV := v.BitLen() <= 8 && (v.Uint64() == 27 || v.Uint64() == 28)
-		if s.chainId.BitLen() > 0 && !stdV {
-			nv := byte((new(big.Int).Sub(v, s.chainIdMul).Uint64()) - 35 + 27)
-			return nv
-		}
-	}
-	return byte(v.Uint64())
-}
-
 // deriveChainId derives the chain id from the given v parameter
 func deriveChainId(v *big.Int) *big.Int {
 	if v.BitLen() <= 64 {
diff --git a/core/types/transaction_test.go b/core/types/transaction_test.go
index ca105566a..4a38462e3 100644
--- a/core/types/transaction_test.go
+++ b/core/types/transaction_test.go
@@ -47,7 +47,7 @@ var (
 		common.FromHex("5544"),
 	).WithSignature(
 		HomesteadSigner{},
-		common.Hex2Bytes("98ff921201554726367d2be8c804a7ff89ccf285ebc57dff8ae4c44b9c19ac4a8887321be575c8095f789dd4c743dfe42c1820f9231f98a962b210e3ac2452a31c"),
+		common.Hex2Bytes("98ff921201554726367d2be8c804a7ff89ccf285ebc57dff8ae4c44b9c19ac4a8887321be575c8095f789dd4c743dfe42c1820f9231f98a962b210e3ac2452a301"),
 	)
 )
 
diff --git a/core/vm/contracts.go b/core/vm/contracts.go
index b45f14724..5cd0d0bb1 100644
--- a/core/vm/contracts.go
+++ b/core/vm/contracts.go
@@ -89,21 +89,15 @@ func ecrecoverFunc(in []byte) []byte {
 
 	r := common.BytesToBig(in[64:96])
 	s := common.BytesToBig(in[96:128])
-	// Treat V as a 256bit integer
-	vbig := common.Bytes2Big(in[32:64])
-	v := byte(vbig.Uint64())
+	v := in[63] - 27
 
 	// tighter sig s values in homestead only apply to tx sigs
-	if !crypto.ValidateSignatureValues(v, r, s, false) {
+	if common.Bytes2Big(in[32:63]).BitLen() > 0 || !crypto.ValidateSignatureValues(v, r, s, false) {
 		glog.V(logger.Detail).Infof("ECRECOVER error: v, r or s value invalid")
 		return nil
 	}
-
-	// v needs to be at the end and normalized for libsecp256k1
-	vbignormal := new(big.Int).Sub(vbig, big.NewInt(27))
-	vnormal := byte(vbignormal.Uint64())
-	rsv := append(in[64:128], vnormal)
-	pubKey, err := crypto.Ecrecover(in[:32], rsv)
+	// v needs to be at the end for libsecp256k1
+	pubKey, err := crypto.Ecrecover(in[:32], append(in[64:128], v))
 	// make sure the public key is a valid one
 	if err != nil {
 		glog.V(logger.Detail).Infoln("ECRECOVER error: ", err)
diff --git a/crypto/crypto.go b/crypto/crypto.go
index e611bd8f4..f1a4b774c 100644
--- a/crypto/crypto.go
+++ b/crypto/crypto.go
@@ -167,25 +167,19 @@ func GenerateKey() (*ecdsa.PrivateKey, error) {
 	return ecdsa.GenerateKey(secp256k1.S256(), rand.Reader)
 }
 
+// ValidateSignatureValues verifies whether the signature values are valid with
+// the given chain rules. The v value is assumed to be either 0 or 1.
 func ValidateSignatureValues(v byte, r, s *big.Int, homestead bool) bool {
 	if r.Cmp(common.Big1) < 0 || s.Cmp(common.Big1) < 0 {
 		return false
 	}
-	vint := uint32(v)
 	// reject upper range of s values (ECDSA malleability)
 	// see discussion in secp256k1/libsecp256k1/include/secp256k1.h
 	if homestead && s.Cmp(secp256k1.HalfN) > 0 {
 		return false
 	}
 	// Frontier: allow s to be in full N range
-	if s.Cmp(secp256k1.N) >= 0 {
-		return false
-	}
-	if r.Cmp(secp256k1.N) < 0 && (vint == 27 || vint == 28) {
-		return true
-	} else {
-		return false
-	}
+	return r.Cmp(secp256k1.N) < 0 && s.Cmp(secp256k1.N) < 0 && (v == 0 || v == 1)
 }
 
 func SigToPub(hash, sig []byte) (*ecdsa.PublicKey, error) {
@@ -199,14 +193,13 @@ func SigToPub(hash, sig []byte) (*ecdsa.PublicKey, error) {
 }
 
 // Sign calculates an ECDSA signature.
+//
 // This function is susceptible to choosen plaintext attacks that can leak
 // information about the private key that is used for signing. Callers must
 // be aware that the given hash cannot be choosen by an adversery. Common
 // solution is to hash any input before calculating the signature.
 //
-// Note: the calculated signature is not Ethereum compliant. The yellow paper
-// dictates Ethereum singature to have a V value with and offset of 27 v in [27,28].
-// Use SignEthereum to get an Ethereum compliant signature.
+// The produced signature is in the [R || S || V] format where V is 0 or 1.
 func Sign(data []byte, prv *ecdsa.PrivateKey) (sig []byte, err error) {
 	if len(data) != 32 {
 		return nil, fmt.Errorf("hash is required to be exactly 32 bytes (%d)", len(data))
@@ -218,20 +211,6 @@ func Sign(data []byte, prv *ecdsa.PrivateKey) (sig []byte, err error) {
 	return
 }
 
-// SignEthereum calculates an Ethereum ECDSA signature.
-// This function is susceptible to choosen plaintext attacks that can leak
-// information about the private key that is used for signing. Callers must
-// be aware that the given hash cannot be freely choosen by an adversery.
-// Common solution is to hash the message before calculating the signature.
-func SignEthereum(data []byte, prv *ecdsa.PrivateKey) ([]byte, error) {
-	sig, err := Sign(data, prv)
-	if err != nil {
-		return nil, err
-	}
-	sig[64] += 27 // as described in the yellow paper
-	return sig, err
-}
-
 func Encrypt(pub *ecdsa.PublicKey, message []byte) ([]byte, error) {
 	return ecies.Encrypt(rand.Reader, ecies.ImportECDSAPublic(pub), message, nil, nil)
 }
diff --git a/crypto/crypto_test.go b/crypto/crypto_test.go
index 80c9a9aae..86a582306 100644
--- a/crypto/crypto_test.go
+++ b/crypto/crypto_test.go
@@ -80,22 +80,15 @@ func Test0Key(t *testing.T) {
 	}
 }
 
-func testSign(signfn func([]byte, *ecdsa.PrivateKey) ([]byte, error), t *testing.T) {
+func TestSign(t *testing.T) {
 	key, _ := HexToECDSA(testPrivHex)
 	addr := common.HexToAddress(testAddrHex)
 
 	msg := Keccak256([]byte("foo"))
-	sig, err := signfn(msg, key)
+	sig, err := Sign(msg, key)
 	if err != nil {
 		t.Errorf("Sign error: %s", err)
 	}
-
-	// signfn can return a recover id of either [0,1] or [27,28].
-	// In the latter case its an Ethereum signature, adjust recover id.
-	if sig[64] == 27 || sig[64] == 28 {
-		sig[64] -= 27
-	}
-
 	recoveredPub, err := Ecrecover(msg, sig)
 	if err != nil {
 		t.Errorf("ECRecover error: %s", err)
@@ -117,34 +110,15 @@ func testSign(signfn func([]byte, *ecdsa.PrivateKey) ([]byte, error), t *testing
 	}
 }
 
-func TestSign(t *testing.T) {
-	testSign(Sign, t)
-}
-
-func TestSignEthereum(t *testing.T) {
-	testSign(SignEthereum, t)
-}
-
-func testInvalidSign(signfn func([]byte, *ecdsa.PrivateKey) ([]byte, error), t *testing.T) {
-	_, err := signfn(make([]byte, 1), nil)
-	if err == nil {
+func TestInvalidSign(t *testing.T) {
+	if _, err := Sign(make([]byte, 1), nil); err == nil {
 		t.Errorf("expected sign with hash 1 byte to error")
 	}
-
-	_, err = signfn(make([]byte, 33), nil)
-	if err == nil {
+	if _, err := Sign(make([]byte, 33), nil); err == nil {
 		t.Errorf("expected sign with hash 33 byte to error")
 	}
 }
 
-func TestInvalidSign(t *testing.T) {
-	testInvalidSign(Sign, t)
-}
-
-func TestInvalidSignEthereum(t *testing.T) {
-	testInvalidSign(SignEthereum, t)
-}
-
 func TestNewContractAddress(t *testing.T) {
 	key, _ := HexToECDSA(testPrivHex)
 	addr := common.HexToAddress(testAddrHex)
@@ -207,38 +181,38 @@ func TestValidateSignatureValues(t *testing.T) {
 	secp256k1nMinus1 := new(big.Int).Sub(secp256k1.N, common.Big1)
 
 	// correct v,r,s
-	check(true, 27, one, one)
-	check(true, 28, one, one)
+	check(true, 0, one, one)
+	check(true, 1, one, one)
 	// incorrect v, correct r,s,
-	check(false, 30, one, one)
-	check(false, 26, one, one)
+	check(false, 2, one, one)
+	check(false, 3, one, one)
 
 	// incorrect v, combinations of incorrect/correct r,s at lower limit
+	check(false, 2, zero, zero)
+	check(false, 2, zero, one)
+	check(false, 2, one, zero)
+	check(false, 2, one, one)
+
+	// correct v for any combination of incorrect r,s
 	check(false, 0, zero, zero)
 	check(false, 0, zero, one)
 	check(false, 0, one, zero)
-	check(false, 0, one, one)
 
-	// correct v for any combination of incorrect r,s
-	check(false, 27, zero, zero)
-	check(false, 27, zero, one)
-	check(false, 27, one, zero)
-
-	check(false, 28, zero, zero)
-	check(false, 28, zero, one)
-	check(false, 28, one, zero)
+	check(false, 1, zero, zero)
+	check(false, 1, zero, one)
+	check(false, 1, one, zero)
 
 	// correct sig with max r,s
-	check(true, 27, secp256k1nMinus1, secp256k1nMinus1)
+	check(true, 0, secp256k1nMinus1, secp256k1nMinus1)
 	// correct v, combinations of incorrect r,s at upper limit
-	check(false, 27, secp256k1.N, secp256k1nMinus1)
-	check(false, 27, secp256k1nMinus1, secp256k1.N)
-	check(false, 27, secp256k1.N, secp256k1.N)
+	check(false, 0, secp256k1.N, secp256k1nMinus1)
+	check(false, 0, secp256k1nMinus1, secp256k1.N)
+	check(false, 0, secp256k1.N, secp256k1.N)
 
 	// current callers ensures r,s cannot be negative, but let's test for that too
 	// as crypto package could be used stand-alone
-	check(false, 27, minusOne, one)
-	check(false, 27, one, minusOne)
+	check(false, 0, minusOne, one)
+	check(false, 0, one, minusOne)
 }
 
 func checkhash(t *testing.T, name string, f func([]byte) []byte, msg, exp []byte) {
diff --git a/internal/ethapi/api.go b/internal/ethapi/api.go
index b84bba516..561e72b01 100644
--- a/internal/ethapi/api.go
+++ b/internal/ethapi/api.go
@@ -287,11 +287,19 @@ func signHash(data []byte) []byte {
 // Sign calculates an Ethereum ECDSA signature for:
 // keccack256("\x19Ethereum Signed Message:\n" + len(message) + message))
 //
+// Note, the produced signature conforms to the secp256k1 curve R, S and V values,
+// where the V value will be 27 or 28 for legacy reasons.
+//
 // The key used to calculate the signature is decrypted with the given password.
 //
 // https://github.com/ethereum/go-ethereum/wiki/Management-APIs#personal_sign
 func (s *PrivateAccountAPI) Sign(ctx context.Context, data hexutil.Bytes, addr common.Address, passwd string) (hexutil.Bytes, error) {
-	return s.b.AccountManager().SignWithPassphrase(addr, passwd, signHash(data))
+	signature, err := s.b.AccountManager().SignWithPassphrase(addr, passwd, signHash(data))
+	if err != nil {
+		return nil, err
+	}
+	signature[64] += 27 // SignWithPassphrase uses canonical secp256k1 signatures (v = 0 or 1), transform to yellow paper
+	return signature, nil
 }
 
 // EcRecover returns the address for the account that was used to create the signature.
@@ -300,15 +308,19 @@ func (s *PrivateAccountAPI) Sign(ctx context.Context, data hexutil.Bytes, addr c
 // hash = keccak256("\x19Ethereum Signed Message:\n"${message length}${message})
 // addr = ecrecover(hash, signature)
 //
+// Note, the signature must conform to the secp256k1 curve R, S and V values, where
+// the V value must be be 27 or 28 for legacy reasons.
+//
 // https://github.com/ethereum/go-ethereum/wiki/Management-APIs#personal_ecRecover
 func (s *PrivateAccountAPI) EcRecover(ctx context.Context, data, sig hexutil.Bytes) (common.Address, error) {
 	if len(sig) != 65 {
 		return common.Address{}, fmt.Errorf("signature must be 65 bytes long")
 	}
-	// see crypto.Ecrecover description
-	if sig[64] == 27 || sig[64] == 28 {
-		sig[64] -= 27
+	if sig[64] != 27 && sig[64] != 28 {
+		return common.Address{}, fmt.Errorf("invalid Ethereum signature (V is not 27 or 28)")
 	}
+	sig[64] -= 27 // Transform yellow paper signatures to canonical secp256k1 form
+
 	rpk, err := crypto.Ecrecover(signHash(data), sig)
 	if err != nil {
 		return common.Address{}, err
@@ -964,7 +976,7 @@ func (s *PublicTransactionPoolAPI) GetTransactionReceipt(txHash common.Hash) (ma
 func (s *PublicTransactionPoolAPI) sign(addr common.Address, tx *types.Transaction) (*types.Transaction, error) {
 	signer := types.MakeSigner(s.b.ChainConfig(), s.b.CurrentBlock().Number())
 
-	signature, err := s.b.AccountManager().SignEthereum(addr, signer.Hash(tx).Bytes())
+	signature, err := s.b.AccountManager().Sign(addr, signer.Hash(tx).Bytes())
 	if err != nil {
 		return nil, err
 	}
@@ -1046,11 +1058,10 @@ func (s *PublicTransactionPoolAPI) SendTransaction(ctx context.Context, args Sen
 	}
 	tx := args.toTransaction()
 	signer := types.MakeSigner(s.b.ChainConfig(), s.b.CurrentBlock().Number())
-	signature, err := s.b.AccountManager().SignEthereum(args.From, signer.Hash(tx).Bytes())
+	signature, err := s.b.AccountManager().Sign(args.From, signer.Hash(tx).Bytes())
 	if err != nil {
 		return common.Hash{}, err
 	}
-
 	return submitTransaction(ctx, s.b, tx, signature)
 }
 
@@ -1084,11 +1095,19 @@ func (s *PublicTransactionPoolAPI) SendRawTransaction(ctx context.Context, encod
 // Sign calculates an ECDSA signature for:
 // keccack256("\x19Ethereum Signed Message:\n" + len(message) + message).
 //
+// Note, the produced signature conforms to the secp256k1 curve R, S and V values,
+// where the V value will be 27 or 28 for legacy reasons.
+//
 // The account associated with addr must be unlocked.
 //
 // https://github.com/ethereum/wiki/wiki/JSON-RPC#eth_sign
 func (s *PublicTransactionPoolAPI) Sign(addr common.Address, data hexutil.Bytes) (hexutil.Bytes, error) {
-	return s.b.AccountManager().SignEthereum(addr, signHash(data))
+	signature, err := s.b.AccountManager().Sign(addr, signHash(data))
+	if err == nil {
+		// Sign uses canonical secp256k1 signatures (v = 0 or 1), transform to yellow paper
+		signature[64] += 27
+	}
+	return signature, err
 }
 
 // SignTransactionResult represents a RLP encoded signed transaction.