C++ :: Forward Declare A Class Template?

i hit the point where i have two class templates that are dependent on each other (in detail, class a stores a pointer of class b), creating a cyclic include issue.

Usually i resolve this with a forward declaration, but i cant seem to figure out how to do it with a template class.In fact, ( i think) i got it to work for this :

Code:
template<typename T>
class a
{
public:
T x;
}

but not for this:

Code:
template<int b>
class b
{
public:
int getb(){return b;}
}

Where the template is not for a specific "type".