non virtual interfaces

[Alexandr Druzhinin]

Hello all.

I try to use NVI and failed with a snippet from TDPL:

interface Transmogrifier
{
	final void thereAndBack()
	{
		transmogrify();
		untransmogrify();
	}

	private:
		void transmogrify();
		void untransmogrify();
}

class CardboardBox: Transmogrifier
{
	override private void transmogrify() { }
	override void untransmogrify() {}
}

int main()
{
	auto cb = new CardboardBox();
	return 0;
}

doesn't compile with log info:
src/test.d(16): Error: function test.CardboardBox.transmogrify cannot 
override a non-virtual function
src/test.d(17): Error: function test.CardboardBox.untransmogrify does 
not override any function, did you mean to override 
'test.Transmogrifier.untransmogrify'?

It rather well differs from what I expected reading TDPL. Something is 
changed very much or I just missed something?