diff --git a/error.go b/error.go
index e1d6dfae..e2848e57 100644
--- a/error.go
+++ b/error.go
@@ -204,11 +204,7 @@ type errorInfo struct {
 }
 
 // map of http handlers for each error string.
-var ErrorMaps map[string]*errorInfo
-
-func init() {
-	ErrorMaps = make(map[string]*errorInfo)
-}
+var ErrorMaps map[string]*errorInfo = make(map[string]*errorInfo, 10)
 
 // show 401 unauthorized error.
 func unauthorized(rw http.ResponseWriter, r *http.Request) {
@@ -392,22 +388,21 @@ func ErrorController(c ControllerInterface) *App {
 }
 
 // show error string as simple text message.
-// if error string is empty, show 500 error as default.
-func exception(errcode string, ctx *context.Context) {
-	code, err := strconv.Atoi(errcode)
-	if err != nil {
-		code = 503
-	}
-	if h, ok := ErrorMaps[errcode]; ok {
-		executeError(h, ctx, code)
-		return
-	} else if h, ok := ErrorMaps["503"]; ok {
-		executeError(h, ctx, code)
-		return
-	} else {
-		ctx.ResponseWriter.WriteHeader(code)
-		ctx.WriteString(errcode)
+// if error string is empty, show 503 or 500 error as default.
+func exception(errCode string, ctx *context.Context) {
+	for ec, _ := range []string{errCode, "503", "500"} {
+		code, _ := strconv.Atoi(errCode)
+		if code == 0 {
+			code = 503
+		}
+		if h, ok := ErrorMaps[ec]; ok {
+			executeError(h, ctx, code)
+			return
+		}
 	}
+	//if 50x error has been removed from errorMap
+	ctx.ResponseWriter.WriteHeader(503)
+	ctx.WriteString(errCode)
 }
 
 func executeError(err *errorInfo, ctx *context.Context, code int) {
diff --git a/hooks.go b/hooks.go
index 178d8dc4..6e401c06 100644
--- a/hooks.go
+++ b/hooks.go
@@ -5,6 +5,8 @@ import (
 	"path/filepath"
 	"strconv"
 
+	"net/http"
+
 	"github.com/astaxie/beego/session"
 )
 
@@ -18,42 +20,22 @@ func registerMime() error {
 
 // register default error http handlers, 404,401,403,500 and 503.
 func registerDefaultErrorHandler() error {
-	if _, ok := ErrorMaps["401"]; !ok {
-		ErrorHandler("401", unauthorized)
-	}
 
-	if _, ok := ErrorMaps["402"]; !ok {
-		ErrorHandler("402", paymentRequired)
-	}
-
-	if _, ok := ErrorMaps["403"]; !ok {
-		ErrorHandler("403", forbidden)
-	}
-
-	if _, ok := ErrorMaps["404"]; !ok {
-		ErrorHandler("404", notFound)
-	}
-
-	if _, ok := ErrorMaps["405"]; !ok {
-		ErrorHandler("405", methodNotAllowed)
-	}
-
-	if _, ok := ErrorMaps["500"]; !ok {
-		ErrorHandler("500", internalServerError)
-	}
-	if _, ok := ErrorMaps["501"]; !ok {
-		ErrorHandler("501", notImplemented)
-	}
-	if _, ok := ErrorMaps["502"]; !ok {
-		ErrorHandler("502", badGateway)
-	}
-
-	if _, ok := ErrorMaps["503"]; !ok {
-		ErrorHandler("503", serviceUnavailable)
-	}
-
-	if _, ok := ErrorMaps["504"]; !ok {
-		ErrorHandler("504", gatewayTimeout)
+	for e, h := range map[string]func(http.ResponseWriter, *http.Request){
+		"401": unauthorized,
+		"402": paymentRequired,
+		"403": forbidden,
+		"404": notFound,
+		"405": methodNotAllowed,
+		"500": internalServerError,
+		"501": notImplemented,
+		"502": badGateway,
+		"503": serviceUnavailable,
+		"504": gatewayTimeout,
+	} {
+		if _, ok := ErrorMaps[e]; !ok {
+			ErrorHandler(e, h)
+		}
 	}
 	return nil
 }