Overloading method in derived class

Hello all,
I know this is a C++ specific question but i don't know how 
to search the answer in google.

I have the following code :
struct Toto { void Add(int x){} };

struct Titi : public Toto { void Add(int x, int y){} };

int main () 

{ 

Titi titi;

titi.Add(1);

}

And both MSVC 7 and gcc give me 

error : 'Titi::Add' : function does not take 1 parameters

sure i could write titi.Toto::Add(1); and this will work but 

i want to avoid such a pain.

is it a C++ specification problem or a compiler problem ?

Thanks

------------------------

Lagarde Sébastien

Neko entertainment