Re: singleton in a DLL loaded class

I have a class loaded from a DLL that I would like to implement as a
multi-threadable singleton. Unfortunately, I seem to still be getting
two distinct instances of this class. It is implemented as below.

//singletonclass.h
class SingletonClass : BaseClass
{
public:
   static SingletonClass& Instance();
   ~SingletonClass();
   //... Implement BaseClass functions
private:
   static std::auto_ptr< SingletonClass > _theInstance;
   static Mutex* _m;
}

//singletonclass.cpp
std::auto_ptr< SingletonClass > SingletonClass::_theInstance;
Mutex* SingletonClass::_m;

/*static*/ SingletonClass& SingletonClass::Instance()
{
   Mutex::Create( &_m );