Function definitions in headers of a DLL

Hi,

first excuse my poor english.

I have a problem with a project, that worked fine under Windows (using
VC7) and Linux (using gcc) until a part of it was put into a DLL.
Since then, the Windows version doesn't work anymore. I've found the
problem, but can't solve it.The context of the problem in the project
is quite complex, hence I isolated it:

There is a DLL which contains a baseclass A, which has a static method
generate_id(). For every call, this method returns a unique id, by
incrementing a static variable. Every subclass of A has a static
method static_id(), which uses generate_id() to get a unique id at its
first call and simply returning this id in every following. The
problem is, that the implementation of static_id() must be in the
class definition in the header file, because the subclasses are
defined by macros.

Under linux this works perfect, even now with a DLL, but under Windows
a subclass has another static_id in the DLL as outside of it (in the
DLL client).

The following code illustrates the problem:

TestDll.h

#define EXPORT __declspec(dllexport)

class A
{
    public:
        EXPORT static int generate_id();
};

class B : public A
{
    public:
        EXPORT static int static_id()
        {
            static int id = 0;
            if( !id )
                id = A::generate_id();

            return id;
        };
};

class Container {
    public:
        EXPORT Container();

        A* a;
};

TestDll.cpp

int A::generate_id()
{
    static int id_counter = 0;
    return ++id_counter;
}

Container::Container()
{
    a = new B();
    cout << ( (B*)a )->static_id();
}

The problem can be seen in the following behaviour of a DLL client:

Container* t = new Container();

returns 1, while the following call of

cout << B::static_id();

returns 2.

I think the reason for that is, that client and DLL are, caused by
inline expansion, using different "instances" of the method
static_id() (if I put the definition of static_id() in the cpp file
everything works fine, but due to the use of macros, I can't do that
in my project, as I said).
But even by using the compiler switch /Ob0 or a #pragma
auto_inline( off ) the microsoft compiler can not be prevented from
that inline expansion. Until today I thought that only to do an inline
expansion is an advice, not that the compiler is forced to do inlining
even if I say not to.

Any suggestions?

Grateful for every help

Marcel