MOC compiler does not support strongly typed enum syntax

Inside a class, I use the Q_ENUMS() macro to include an enumeration in Qt's meta-object system. I noticed that if I used the strongly typed enums feature from c++11, the moc compiler no longer includes the enum information into the generated .cxx file.

example 1:
class example1 : public QObject
{
Q_ENUMS( enum1 )

public:
enum enum1

{ enum1Val1 = 0, enum1Val2 }

;
};

example 2:
class example2 : public QObject
{
Q_ENUMS( enum2 )

public:
enum enum2 : int

{ enum2Val1 = 0, enum2Val2 }

;
};

example 3:
class example3 : public QObject
{
Q_ENUMS( enum3 )

public:
enum class enum3

{ enum3Val1 = 0, enum3Val2 }

;
};

example 4:
class example4 : public QObject
{
Q_ENUMS( enum4 )

public:
enum class enum4 : int

{ enum4Val1 = 0, enum4Val2 }

;
};

Example 1 works with the moc compiler but examples 2, 3, and 4 do not. The code for examples for 2, 3, and 4 are valid for c++11.