diff --git a/cmd/geth/admin.go b/cmd/geth/admin.go
index bd09291bff2bf4d96a87795f0e6548dc80b5f108..e75ff047abbc32631b3cdc9107f36be35ad9104f 100644
--- a/cmd/geth/admin.go
+++ b/cmd/geth/admin.go
@@ -3,7 +3,6 @@ package main
 import (
 	"errors"
 	"fmt"
-	"os"
 	"time"
 
 	"github.com/ethereum/go-ethereum/cmd/utils"
@@ -318,7 +317,7 @@ func (js *jsre) newAccount(call otto.FunctionCall) otto.Value {
 		fmt.Printf("Could not create the account: %v", err)
 		return otto.UndefinedValue()
 	}
-	return js.re.ToVal(common.Bytes2Hex(acct.Address))
+	return js.re.ToVal("0x" + common.Bytes2Hex(acct.Address))
 }
 
 func (js *jsre) nodeInfo(call otto.FunctionCall) otto.Value {
@@ -334,33 +333,15 @@ func (js *jsre) importChain(call otto.FunctionCall) otto.Value {
 		fmt.Println("err: require file name")
 		return otto.FalseValue()
 	}
-
 	fn, err := call.Argument(0).ToString()
 	if err != nil {
 		fmt.Println(err)
 		return otto.FalseValue()
 	}
-
-	var fh *os.File
-	fh, err = os.OpenFile(fn, os.O_RDONLY, os.ModePerm)
-	if err != nil {
-		fmt.Println(err)
+	if err := utils.ImportChain(js.ethereum.ChainManager(), fn); err != nil {
+		fmt.Println("Import error: ", err)
 		return otto.FalseValue()
 	}
-	defer fh.Close()
-
-	var blocks types.Blocks
-	if err = rlp.Decode(fh, &blocks); err != nil {
-		fmt.Println(err)
-		return otto.FalseValue()
-	}
-
-	js.ethereum.ChainManager().Reset()
-	if err = js.ethereum.ChainManager().InsertChain(blocks); err != nil {
-		fmt.Println(err)
-		return otto.FalseValue()
-	}
-
 	return otto.TrueValue()
 }
 
diff --git a/cmd/geth/js_test.go b/cmd/geth/js_test.go
index 4421b1d6808bf6823bba2963b6d3735734d4006b..5210391212a940845e3081b183bcfd2ebc18a99c 100644
--- a/cmd/geth/js_test.go
+++ b/cmd/geth/js_test.go
@@ -3,260 +3,141 @@ package main
 import (
 	"fmt"
 	"io/ioutil"
+	"path/filepath"
 	"os"
 	"path"
 	"testing"
 
-	"github.com/robertkrimen/otto"
-
 	"github.com/ethereum/go-ethereum/accounts"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/eth"
+	"runtime"
+	"regexp"
+	"strconv"
 )
 
 var port = 30300
 
-func testJEthRE(t *testing.T) (repl *jsre, ethereum *eth.Ethereum, err error) {
-	os.RemoveAll("/tmp/eth/")
-	err = os.MkdirAll("/tmp/eth/keys/e273f01c99144c438695e10f24926dc1f9fbf62d/", os.ModePerm)
-	if err != nil {
-		t.Errorf("%v", err)
-		return
-	}
-	err = os.MkdirAll("/tmp/eth/data", os.ModePerm)
+func testJEthRE(t *testing.T) (*jsre, *eth.Ethereum) {
+	tmp, err := ioutil.TempDir("", "geth-test")
 	if err != nil {
-		t.Errorf("%v", err)
-		return
+		t.Fatal(err)
 	}
-	// FIXME: this does not work ATM
-	ks := crypto.NewKeyStorePlain("/tmp/eth/keys")
-	ioutil.WriteFile("/tmp/eth/keys/e273f01c99144c438695e10f24926dc1f9fbf62d/e273f01c99144c438695e10f24926dc1f9fbf62d",
-		[]byte(`{"Id":"RhRXD+fNRKS4jx+7ZfEsNA==","Address":"4nPwHJkUTEOGleEPJJJtwfn79i0=","PrivateKey":"h4ACVpe74uIvi5Cg/2tX/Yrm2xdr3J7QoMbMtNX2CNc="}`), os.ModePerm)
+	defer os.RemoveAll(tmp)
 
-	port++
-	ethereum, err = eth.New(&eth.Config{
-		DataDir:        "/tmp/eth",
+	ks := crypto.NewKeyStorePlain(filepath.Join(tmp, "keys"))
+	ethereum, err := eth.New(&eth.Config{
+		DataDir:        tmp,
 		AccountManager: accounts.NewManager(ks),
-		Port:           fmt.Sprintf("%d", port),
-		MaxPeers:       10,
+		MaxPeers:       0,
 		Name:           "test",
 	})
-
 	if err != nil {
-		t.Errorf("%v", err)
-		return
+		t.Fatal("%v", err)
 	}
 	assetPath := path.Join(os.Getenv("GOPATH"), "src", "github.com", "ethereum", "go-ethereum", "cmd", "mist", "assets", "ext")
-	repl = newJSRE(ethereum, assetPath, false)
-	return
+	repl := newJSRE(ethereum, assetPath, false)
+	return repl, ethereum
 }
 
 func TestNodeInfo(t *testing.T) {
-	repl, ethereum, err := testJEthRE(t)
-	if err != nil {
-		t.Errorf("error creating jsre, got %v", err)
-		return
-	}
-	err = ethereum.Start()
-	if err != nil {
-		t.Errorf("error starting ethereum: %v", err)
-		return
+	repl, ethereum := testJEthRE(t)
+	if err := ethereum.Start(); err != nil {
+		t.Fatalf("error starting ethereum: %v", err)
 	}
 	defer ethereum.Stop()
 
-	val, err := repl.re.Run("admin.nodeInfo()")
-	if err != nil {
-		t.Errorf("expected no error, got %v", err)
-	}
-	exp, err := val.Export()
-	if err != nil {
-		t.Errorf("expected no error, got %v", err)
-	}
-	nodeInfo, ok := exp.(*eth.NodeInfo)
-	if !ok {
-		t.Errorf("expected nodeInfo, got %v", err)
-	}
-	exp = "test"
-	got := nodeInfo.Name
-	if exp != got {
-		t.Errorf("expected %v, got %v", exp, got)
-	}
-	exp = 30301
-	port := nodeInfo.DiscPort
-	if exp != port {
-		t.Errorf("expected %v, got %v", exp, port)
-	}
-	exp = 30301
-	port = nodeInfo.TCPPort
-	if exp != port {
-		t.Errorf("expected %v, got %v", exp, port)
-	}
+	want := `{"DiscPort":0,"IP":"0.0.0.0","ListenAddr":"","Name":"test","NodeID":"00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000","NodeUrl":"enode://00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000@0.0.0.0:0","TCPPort":0,"Td":"0"}`
+	checkEvalJSON(t, repl, `admin.nodeInfo()`, want)
 }
 
 func TestAccounts(t *testing.T) {
-	repl, ethereum, err := testJEthRE(t)
-	if err != nil {
-		t.Errorf("error creating jsre, got %v", err)
-		return
-	}
-	err = ethereum.Start()
-	if err != nil {
-		t.Errorf("error starting ethereum: %v", err)
-		return
+	repl, ethereum := testJEthRE(t)
+	if err := ethereum.Start(); err != nil {
+		t.Fatalf("error starting ethereum: %v", err)
 	}
 	defer ethereum.Stop()
 
-	val, err := repl.re.Run("eth.coinbase")
-	if err != nil {
-		t.Errorf("expected no error, got %v", err)
-	}
-
-	pp, err := repl.re.PrettyPrint(val)
-	if err != nil {
-		t.Errorf("%v", err)
-	}
-
-	if !val.IsString() {
-		t.Errorf("incorrect type, expected string, got %v: %v", val, pp)
-	}
-	strVal, _ := val.ToString()
-	expected := "0xe273f01c99144c438695e10f24926dc1f9fbf62d"
-	if strVal != expected {
-		t.Errorf("incorrect result, expected %s, got %v", expected, strVal)
-	}
+	checkEvalJSON(t, repl, `eth.accounts`, `[]`)
+	checkEvalJSON(t, repl, `eth.coinbase`, `"0x"`)
 
-	val, err = repl.re.Run(`admin.newAccount("password")`)
+	val, err := repl.re.Run(`admin.newAccount("password")`)
 	if err != nil {
 		t.Errorf("expected no error, got %v", err)
 	}
-	addr, err := val.ToString()
-	if err != nil {
-		t.Errorf("expected string, got %v", err)
-	}
-
-	val, err = repl.re.Run("eth.accounts")
-	if err != nil {
-		t.Errorf("expected no error, got %v", err)
-	}
-	exp, err := val.Export()
-	if err != nil {
-		t.Errorf("expected no error, got %v", err)
-	}
-	interfaceAddr, ok := exp.([]interface{})
-	if !ok {
-		t.Errorf("expected []string, got %T", exp)
-	}
-
-	addrs := make([]string, len(interfaceAddr))
-	for i, addr := range interfaceAddr {
-		var ok bool
-		if addrs[i], ok = addr.(string); !ok {
-			t.Errorf("expected addrs[%d] to be string. Got %T instead", i, addr)
-		}
-	}
-
-	if len(addrs) != 2 || (addr != addrs[0][2:] && addr != addrs[1][2:]) {
-		t.Errorf("expected addrs == [<default>, <new>], got %v (%v)", addrs, addr)
+	addr := val.String()
+	if !regexp.MustCompile(`0x[0-9a-f]{40}`).MatchString(addr) {
+		t.Errorf("address not hex: %q", addr)
 	}
 
+	checkEvalJSON(t, repl, `eth.accounts`, `["` + addr + `"]`)
+	checkEvalJSON(t, repl, `eth.coinbase`, `"` + addr + `"`)
 }
 
 func TestBlockChain(t *testing.T) {
-	repl, ethereum, err := testJEthRE(t)
-	if err != nil {
-		t.Errorf("error creating jsre, got %v", err)
-		return
-	}
-	err = ethereum.Start()
-	if err != nil {
-		t.Errorf("error starting ethereum: %v", err)
-		return
+	repl, ethereum := testJEthRE(t)
+	if err := ethereum.Start(); err != nil {
+		t.Fatalf("error starting ethereum: %v", err)
 	}
 	defer ethereum.Stop()
 
-	// should get current block
-	val0, err := repl.re.Run("admin.debug.dumpBlock()")
+	// get current block dump before export/import.
+	val, err := repl.re.Run("JSON.stringify(admin.debug.dumpBlock())")
 	if err != nil {
 		t.Errorf("expected no error, got %v", err)
 	}
+	beforeExport := val.String()
 
-	fn := "/tmp/eth/data/blockchain.0"
-	_, err = repl.re.Run("admin.export(\"" + fn + "\")")
+	// do the export
+	tmp, err := ioutil.TempDir("", "geth-test-export")
 	if err != nil {
-		t.Errorf("expected no error, got %v", err)
-	}
-	if _, err = os.Stat(fn); err != nil {
-		t.Errorf("expected no error on file, got %v", err)
+		t.Fatal(err)
 	}
+	defer os.RemoveAll(tmp)
+	tmpfile := filepath.Join(tmp, "export.chain")
+	tmpfileq := strconv.Quote(tmpfile)
 
-	_, err = repl.re.Run("admin.import(\"" + fn + "\")")
-	if err != nil {
-		t.Errorf("expected no error, got %v", err)
+	checkEvalJSON(t, repl, `admin.export(` + tmpfileq + `)`, `true`)
+	if _, err := os.Stat(tmpfile); err != nil {
+		t.Fatal(err)
 	}
 
-	var val1 otto.Value
-
-	// should get current block
-	val1, err = repl.re.Run("admin.debug.dumpBlock()")
-	if err != nil {
-		t.Errorf("expected no error, got %v", err)
-	}
-
-	// FIXME: neither != , nor reflect.DeepEqual works, doing string comparison
-	v0 := fmt.Sprintf("%v", val0)
-	v1 := fmt.Sprintf("%v", val1)
-	if v0 != v1 {
-		t.Errorf("expected same head after export-import, got %v (!=%v)", v1, v0)
-	}
+	// check import, verify that dumpBlock gives the same result.
+	checkEvalJSON(t, repl, `admin.import(` + tmpfileq + `)`, `true`)
+	checkEvalJSON(t, repl, `admin.debug.dumpBlock()`, beforeExport)
 }
 
 func TestMining(t *testing.T) {
-	repl, ethereum, err := testJEthRE(t)
-	if err != nil {
-		t.Errorf("error creating jsre, got %v", err)
-		return
-	}
-	err = ethereum.Start()
-	if err != nil {
-		t.Errorf("error starting ethereum: %v", err)
-		return
+	repl, ethereum := testJEthRE(t)
+	if err := ethereum.Start(); err != nil {
+		t.Fatalf("error starting ethereum: %v", err)
 	}
 	defer ethereum.Stop()
 
-	val, err := repl.re.Run("eth.mining")
-	if err != nil {
-		t.Errorf("expected no error, got %v", err)
-	}
-	var mining bool
-	mining, err = val.ToBoolean()
-	if err != nil {
-		t.Errorf("expected boolean, got %v", err)
-	}
-	if mining {
-		t.Errorf("expected false (not mining), got true")
-	}
-
+	checkEvalJSON(t, repl, `eth.mining`, `false`)
 }
 
 func TestRPC(t *testing.T) {
-	repl, ethereum, err := testJEthRE(t)
-	if err != nil {
-		t.Errorf("error creating jsre, got %v", err)
-		return
-	}
-	err = ethereum.Start()
-	if err != nil {
+	repl, ethereum := testJEthRE(t)
+	if err := ethereum.Start(); err != nil {
 		t.Errorf("error starting ethereum: %v", err)
 		return
 	}
 	defer ethereum.Stop()
 
-	val, err := repl.re.Run(`admin.startRPC("127.0.0.1", 5004)`)
-	if err != nil {
-		t.Errorf("expected no error, got %v", err)
+	checkEvalJSON(t, repl, `admin.startRPC("127.0.0.1", 5004)`, `true`)
+}
+
+func checkEvalJSON(t *testing.T, re *jsre, expr, want string) error {
+	val, err := re.re.Run("JSON.stringify("+ expr + ")")
+	if err == nil && val.String() != want {
+		err = fmt.Errorf("Output mismatch for `%s`:\ngot:  %s\nwant: %s", expr, val.String(), want)
 	}
-	success, _ := val.ToBoolean()
-	if !success {
-		t.Errorf("expected true (started), got false")
+	if err != nil {
+		_, file, line, _ := runtime.Caller(1)
+		file = path.Base(file)
+		fmt.Printf("\t%s:%d: %v\n", file, line, err)
+		t.Fail()
 	}
+	return err
 }