diff --git a/accounts/account_manager.go b/accounts/account_manager.go
index 6cbd23c4e92ceda4e68120c681a55e5dc1e0c2e7..13f16296a81048114664ebf4a4fa442bcb433937 100644
--- a/accounts/account_manager.go
+++ b/accounts/account_manager.go
@@ -49,6 +49,11 @@ var (
 	ErrNoKeys = errors.New("no keys in store")
 )
 
+const (
+    // Default unlock duration (in seconds) when an account is unlocked from the console
+    DefaultAccountUnlockDuration = 300
+)
+
 type Account struct {
 	Address common.Address
 }
diff --git a/cmd/geth/admin.go b/cmd/geth/admin.go
index 15923c3663992009ff7a8bd405944686995596ea..91a336cbbe4a0302f2bf4d0d571791d6828fd4fc 100644
--- a/cmd/geth/admin.go
+++ b/cmd/geth/admin.go
@@ -8,6 +8,7 @@ import (
 	"strconv"
 	"time"
 
+	"github.com/ethereum/go-ethereum/accounts"
 	"github.com/ethereum/go-ethereum/cmd/utils"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/compiler"
@@ -374,6 +375,10 @@ func (js *jsre) unlock(call otto.FunctionCall) otto.Value {
 		fmt.Println(err)
 		return otto.FalseValue()
 	}
+	if seconds == 0 {
+		seconds = accounts.DefaultAccountUnlockDuration
+	}
+
 	arg := call.Argument(1)
 	var passphrase string
 	if arg.IsUndefined() {