static member variables and DLLS

Hi,

I have run into similar problems before and have used convoluted
strategies to resolve the issue. This time I want to undertand this
problem better. I have the following scenario.

My dll has the files A.cpp, B.hpp and someother_file.cpp
/// A.hpp

EXPORT_CLASS class A : public B
{
   public:
      static const char *flag_;

      virtual const char* flag() { return A::flag_; }

}

/// B.hpp
EXPORT_CLASS class B
{
  public:
    virtual const char * flag() = 0;
}

///// somother_file.cpp
#include "A.hpp"

void test(B& b)
{
   if( b->flag() == A::flag_ )
   {
        //// Do something...
   }
}

/// main.cpp
#include <factory.hpp>

int main(int argc, char *argv[])
{
    B* b = factory_create_a();
    test(*b);
}

The issue is that the condition b->flag() == A::flag_ fails. I have
looked at the dissasembly and the addresses being compared are
different, i.e. b->flag() returns ad different address than A::flag_.

It would be great to get an Idea of what is going on here?