Overloading Global operator new in C++

Hello All I overloaded the global operator new to act in a certain manner when provided with additional arguments.

class key{};

void* operator new(size_t sz, key&)
{
    //do some stuff
    return ::operator new(sz);
};

This works fine, except for classes for which operator new is already overloaded.

class test
{
public:
	void* operator new(size_t sz)
	{
		cout << "using custom new"<<endl;
		return ::operator new(sz);
	};
};

int main(int argc, char* argv[])
{
	k k1;
	int*  p_int = new(k1) int;\\ok
        test* p_test1 = new test;\\ok
        test* p_test2 = new(k1) test;\\error
        test* p_test3 = ::new(k1) test;\\ok, but doesn't use test's operator new
	return 0;
}

I am compiling using VC++ 6 and the error I get is: error C2660: 'new' : function does not take 2 parameters Is there a way to support creating my custom new without affecting user class defined new? thanks