Derivable singleton implementation

I have a generic Singleton class.

//Singleton.h

template <class TYPE>
class CSingleTon
{
protected:
    CSingleTon()
    {}

    virtual ~CSingleTon(){}

public:
    static TYPE* Instance()
    {
        if( NULL == m_pInstance )
            m_pInstance = new TYPE();

        return m_pInstance;
    }

    static void Destroy()
    {
        delete m_pInstance;
        m_pInstance = NULL;
    }

protected:
    static TYPE* m_pInstance;
};

template <class TYPE>
TYPE* CSingleTon<TYPE>::m_pInstance = NULL;

#define SET_SINGLETON( classname ) friend class CSingleTon<classname>;

//end of file Singleton.h

And I uses this class to create singletone classes
like

class CGlobalDataStore : public CSingleTon<CGlobalDataStore>
{
    SET_SINGLETON(CGlobalDataStore);
};

This is working correctly.

Now I want to derive a class from CGlobalDataStore( which is also
singleton).
I tried

class CGlobalSignalStore : public CGlobalDataStore
{
    SET_SINGLETON(CGlobalSignalStore);
};

But compilation fails showing error.
error C2440: 'initializing' : cannot convert from 'CGlobalDataStore *'
to 'CGlobalSignalStore *'
1> Cast from base to derived requires dynamic_cast or
static_cast

int main(int argc, char *argv[])
{
    //This line working correctly
    CGlobalDataStore* pGlobalDataStore = CGlobalDataStore::Instance();
    //This shows the error
    CGlobalSignalStore* pGlobalSignalStore = CGlobalSignalStore::Instance
();

    return 0;
}

So my question is, How can I implement a derivable singleton class.