undefined value of enum in derived class

#include <QObject>

class Human : public QObject
{
    Q_OBJECT
    Q_ENUMS(Gender)

public:
    Human() : QObject() {}

    enum Gender {
        Male,
        Female
    };
};

#include "human.h"

class Female : public Human
{
    // Q_OBJECT compile error!
    Q_ENUMS(Brain)
public:
    enum Brain {
        Smart,
        Stupid
    };

    Female() : Human() {}
};

#include <QApplication>
#include "qmlapplicationviewer.h"

#include "female.h"

#include <qdeclarative.h>

Q_DECL_EXPORT int main(int argc, char *argv[])
{
    QScopedPointer<QApplication> app(createApplication(argc, argv));

    qmlRegisterType<Female>("factory.inc.models", 1, 0, "Female");

    QmlApplicationViewer viewer;
    viewer.setOrientation(QmlApplicationViewer::ScreenOrientationAuto);
    viewer.setMainQmlFile(QLatin1String("qml/test/main.qml"));
    viewer.showExpanded();

    return app->exec();
}

import QtQuick 1.0

import factory.inc.models 1.0

Rectangle {
    width: 360
    height: 360

    Component.onCompleted: {
        console.log(Female.Male); // 0
        console.log(Female.Female); // 1

        console.log(Female.Smart); // undefined
        console.log(Female.Stupid); // undefined
    }
}