diff --git a/accounts/account_manager.go b/accounts/account_manager.go
index eb2672a7d..17b128e9e 100644
--- a/accounts/account_manager.go
+++ b/accounts/account_manager.go
@@ -36,6 +36,7 @@ import (
 	"crypto/ecdsa"
 	crand "crypto/rand"
 	"errors"
+	"fmt"
 	"os"
 	"sync"
 	"time"
@@ -158,6 +159,20 @@ func (am *Manager) NewAccount(auth string) (Account, error) {
 	return Account{Address: key.Address}, nil
 }
 
+func (am *Manager) AddressByIndex(index int) (addr string, err error) {
+	var addrs []common.Address
+	addrs, err = am.keyStore.GetKeyAddresses()
+	if err != nil {
+		return
+	}
+	if index < 0 || index >= len(addrs) {
+		err = fmt.Errorf("index out of range: %d (should be 0-%d)", index, len(addrs)-1)
+	} else {
+		addr = addrs[index].Hex()
+	}
+	return
+}
+
 func (am *Manager) Accounts() ([]Account, error) {
 	addresses, err := am.keyStore.GetKeyAddresses()
 	if os.IsNotExist(err) {
@@ -204,6 +219,19 @@ func (am *Manager) Import(path string, keyAuth string) (Account, error) {
 	return Account{Address: key.Address}, nil
 }
 
+func (am *Manager) Update(addr common.Address, authFrom, authTo string) (err error) {
+	var key *crypto.Key
+	key, err = am.keyStore.GetKey(addr, authFrom)
+
+	if err == nil {
+		err = am.keyStore.StoreKey(key, authTo)
+		if err == nil {
+			am.keyStore.Cleanup(addr)
+		}
+	}
+	return
+}
+
 func (am *Manager) ImportPreSaleKey(keyJSON []byte, password string) (acc Account, err error) {
 	var key *crypto.Key
 	key, err = crypto.ImportPreSaleKey(am.keyStore, keyJSON, password)
diff --git a/cmd/geth/main.go b/cmd/geth/main.go
index 673a08d45..ffd26a7c2 100644
--- a/cmd/geth/main.go
+++ b/cmd/geth/main.go
@@ -189,6 +189,33 @@ Note, this is meant to be used for testing only, it is a bad idea to save your
 password to file or expose in any other way.
 					`,
 				},
+				{
+					Action: accountUpdate,
+					Name:   "update",
+					Usage:  "update an existing account",
+					Description: `
+
+    ethereum account update <address>
+
+Update an existing account.
+
+The account is saved in the newest version in encrypted format, you are prompted
+for a passphrase to unlock the account and another to save the updated file.
+
+This same command can therefore be used to migrate an account of a deprecated
+format to the newest format or change the password for an account.
+
+For non-interactive use the passphrase can be specified with the --password flag:
+
+    ethereum --password <passwordfile> account new
+
+Since only one password can be given, only format update can be performed,
+changing your password is only possible interactively.
+
+Note that account update has the a side effect that the order of your accounts
+changes.
+					`,
+				},
 				{
 					Action: accountImport,
 					Name:   "import",
@@ -433,19 +460,30 @@ func execJSFiles(ctx *cli.Context) {
 	ethereum.WaitForShutdown()
 }
 
-func unlockAccount(ctx *cli.Context, am *accounts.Manager, account string, i int) {
+func unlockAccount(ctx *cli.Context, am *accounts.Manager, addr string, i int) (addrHex, auth string) {
 	var err error
 	// Load startup keys. XXX we are going to need a different format
 
-	if !((len(account) == 40) || (len(account) == 42)) { // with or without 0x
-		utils.Fatalf("Invalid account address '%s'", account)
+	if !((len(addr) == 40) || (len(addr) == 42)) { // with or without 0x
+		var index int
+		index, err = strconv.Atoi(addr)
+		if err != nil {
+			utils.Fatalf("Invalid account address '%s'", addr)
+		}
+
+		addrHex, err = am.AddressByIndex(index)
+		if err != nil {
+			utils.Fatalf("%v", err)
+		}
+	} else {
+		addrHex = addr
 	}
 	// Attempt to unlock the account 3 times
 	attempts := 3
 	for tries := 0; tries < attempts; tries++ {
-		msg := fmt.Sprintf("Unlocking account %s | Attempt %d/%d", account, tries+1, attempts)
-		passphrase := getPassPhrase(ctx, msg, false, i)
-		err = am.Unlock(common.HexToAddress(account), passphrase)
+		msg := fmt.Sprintf("Unlocking account %s | Attempt %d/%d", addr, tries+1, attempts)
+		auth = getPassPhrase(ctx, msg, false, i)
+		err = am.Unlock(common.HexToAddress(addrHex), auth)
 		if err == nil {
 			break
 		}
@@ -453,7 +491,8 @@ func unlockAccount(ctx *cli.Context, am *accounts.Manager, account string, i int
 	if err != nil {
 		utils.Fatalf("Unlock account failed '%v'", err)
 	}
-	fmt.Printf("Account '%s' unlocked.\n", account)
+	fmt.Printf("Account '%s' unlocked.\n", addr)
+	return
 }
 
 func blockRecovery(ctx *cli.Context) {
@@ -578,6 +617,21 @@ func accountCreate(ctx *cli.Context) {
 	fmt.Printf("Address: %x\n", acct)
 }
 
+func accountUpdate(ctx *cli.Context) {
+	am := utils.MakeAccountManager(ctx)
+	arg := ctx.Args().First()
+	if len(arg) == 0 {
+		utils.Fatalf("account address or index must be given as argument")
+	}
+
+	addr, authFrom := unlockAccount(ctx, am, arg, 0)
+	authTo := getPassPhrase(ctx, "Please give a new password. Do not forget this password.", true, 0)
+	err := am.Update(common.HexToAddress(addr), authFrom, authTo)
+	if err != nil {
+		utils.Fatalf("Could not update the account: %v", err)
+	}
+}
+
 func importWallet(ctx *cli.Context) {
 	keyfile := ctx.Args().First()
 	if len(keyfile) == 0 {
diff --git a/crypto/key_store_passphrase.go b/crypto/key_store_passphrase.go
index d26e3407f..47909bc76 100644
--- a/crypto/key_store_passphrase.go
+++ b/crypto/key_store_passphrase.go
@@ -72,16 +72,19 @@ func (ks keyStorePassphrase) GenerateNewKey(rand io.Reader, auth string) (key *K
 }
 
 func (ks keyStorePassphrase) GetKey(keyAddr common.Address, auth string) (key *Key, err error) {
-	keyBytes, keyId, err := decryptKeyFromFile(ks, keyAddr, auth)
-	if err != nil {
-		return nil, err
+	keyBytes, keyId, err := decryptKeyFromFile(ks.keysDirPath, keyAddr, auth)
+	if err == nil {
+		key = &Key{
+			Id:         uuid.UUID(keyId),
+			Address:    keyAddr,
+			PrivateKey: ToECDSA(keyBytes),
+		}
 	}
-	key = &Key{
-		Id:         uuid.UUID(keyId),
-		Address:    keyAddr,
-		PrivateKey: ToECDSA(keyBytes),
-	}
-	return key, err
+	return
+}
+
+func (ks keyStorePassphrase) Cleanup(keyAddr common.Address) (err error) {
+	return cleanup(ks.keysDirPath, keyAddr)
 }
 
 func (ks keyStorePassphrase) GetKeyAddresses() (addresses []common.Address, err error) {
@@ -142,7 +145,7 @@ func (ks keyStorePassphrase) StoreKey(key *Key, auth string) (err error) {
 
 func (ks keyStorePassphrase) DeleteKey(keyAddr common.Address, auth string) (err error) {
 	// only delete if correct passphrase is given
-	_, _, err = decryptKeyFromFile(ks, keyAddr, auth)
+	_, _, err = decryptKeyFromFile(ks.keysDirPath, keyAddr, auth)
 	if err != nil {
 		return err
 	}
@@ -150,25 +153,25 @@ func (ks keyStorePassphrase) DeleteKey(keyAddr common.Address, auth string) (err
 	return deleteKey(ks.keysDirPath, keyAddr)
 }
 
-func decryptKeyFromFile(ks keyStorePassphrase, keyAddr common.Address, auth string) (keyBytes []byte, keyId []byte, err error) {
+func decryptKeyFromFile(keysDirPath string, keyAddr common.Address, auth string) (keyBytes []byte, keyId []byte, err error) {
+	fmt.Printf("%v\n", keyAddr.Hex())
 	m := make(map[string]interface{})
-	err = getKey(ks.keysDirPath, keyAddr, &m)
+	err = getKey(keysDirPath, keyAddr, &m)
 	if err != nil {
-		fmt.Printf("get key error: %v\n", err)
 		return
 	}
 
 	v := reflect.ValueOf(m["version"])
 	if v.Kind() == reflect.String && v.String() == "1" {
 		k := new(encryptedKeyJSONV1)
-		getKey(ks.keysDirPath, keyAddr, &k)
+		err = getKey(keysDirPath, keyAddr, &k)
 		if err != nil {
 			return
 		}
 		return decryptKeyV1(k, auth)
 	} else {
 		k := new(encryptedKeyJSONV3)
-		getKey(ks.keysDirPath, keyAddr, &k)
+		err = getKey(keysDirPath, keyAddr, &k)
 		if err != nil {
 			return
 		}
diff --git a/crypto/key_store_plain.go b/crypto/key_store_plain.go
index d785fdf68..c13c5e7a4 100644
--- a/crypto/key_store_plain.go
+++ b/crypto/key_store_plain.go
@@ -43,6 +43,7 @@ type KeyStore interface {
 	GetKeyAddresses() ([]common.Address, error)  // get all addresses
 	StoreKey(*Key, string) error                 // store key optionally using auth string
 	DeleteKey(common.Address, string) error      // delete key by addr and auth string
+	Cleanup(keyAddr common.Address) (err error)
 }
 
 type keyStorePlain struct {
@@ -86,6 +87,10 @@ func (ks keyStorePlain) GetKeyAddresses() (addresses []common.Address, err error
 	return getKeyAddresses(ks.keysDirPath)
 }
 
+func (ks keyStorePlain) Cleanup(keyAddr common.Address) (err error) {
+	return cleanup(ks.keysDirPath, keyAddr)
+}
+
 func (ks keyStorePlain) StoreKey(key *Key, auth string) (err error) {
 	keyJSON, err := json.Marshal(key)
 	if err != nil {
@@ -100,10 +105,14 @@ func (ks keyStorePlain) DeleteKey(keyAddr common.Address, auth string) (err erro
 }
 
 func deleteKey(keysDirPath string, keyAddr common.Address) (err error) {
-	var keyFilePath string
-	keyFilePath, err = getKeyFilePath(keysDirPath, keyAddr)
+	var path string
+	path, err = getKeyFilePath(keysDirPath, keyAddr)
 	if err == nil {
-		err = os.Remove(keyFilePath)
+		addrHex := hex.EncodeToString(keyAddr[:])
+		if path == filepath.Join(keysDirPath, addrHex, addrHex) {
+			path = filepath.Join(keysDirPath, addrHex)
+		}
+		err = os.RemoveAll(path)
 	}
 	return
 }
@@ -122,6 +131,36 @@ func getKeyFilePath(keysDirPath string, keyAddr common.Address) (keyFilePath str
 	return
 }
 
+func cleanup(keysDirPath string, keyAddr common.Address) (err error) {
+	fileInfos, err := ioutil.ReadDir(keysDirPath)
+	if err != nil {
+		return
+	}
+	var paths []string
+	account := hex.EncodeToString(keyAddr[:])
+	for _, fileInfo := range fileInfos {
+		path := filepath.Join(keysDirPath, fileInfo.Name())
+		if len(path) >= 40 {
+			addr := path[len(path)-40 : len(path)]
+			if addr == account {
+				if path == filepath.Join(keysDirPath, addr, addr) {
+					path = filepath.Join(keysDirPath, addr)
+				}
+				paths = append(paths, path)
+			}
+		}
+	}
+	if len(paths) > 1 {
+		for i := 0; err == nil && i < len(paths)-1; i++ {
+			err = os.RemoveAll(paths[i])
+			if err != nil {
+				break
+			}
+		}
+	}
+	return
+}
+
 func getKeyFile(keysDirPath string, keyAddr common.Address) (fileContent []byte, err error) {
 	var keyFilePath string
 	keyFilePath, err = getKeyFilePath(keysDirPath, keyAddr)