Thread: illegal references in static member functions

my class has a static member window procedure. from this procedure i cant refer to any data members of that class without the compiler telling me:

illegal reference to data member 'cBen::value' in a static member function

ie:

Code:

class cBen
{
public:
    static LRESULT CALLBACK WndProc(...);
    int value;
};

LRESULT CALLBACK cBen::WndProc(...)
{
    value=5;
    return DefWindowProc(...);
}

what can i do?