Why can't Class View handle enum parameters?

[rick pdi]

Given this class definition:
class A
{
public:
A();
~A();


enum ENUM_X { X1, X2 };

void TestFunction( ENUM_X x );
};


And this implementation of TestFunction():
void A::TestFunction( A::ENUM_X x )
{
}

or alternatively:
void A::TestFunction( ENUM_X x )
{
}


Why is Developer Studio never able to locate the implementation of A::TestFunction() when clicking on it in Class View?