vector<MyTemplate<MyClass>> not possible?

["Evert, F.K. van" <F dot K dot vanEvert at plant dot wag-ur dot nl>]

When I put instances of a template-derived class in a STL vector, g++ gives
me the following error message (Cygwin/g++3.2 as well as Suse8.0/g++2.95.3):

/usr/include/c++/3.2/bits/stl_construct.h:78: passing `const SmartPtr<CX>'
as
   `this' argument of `SmartPtr<T>::operator T*() [with T = CX]' discards
   qualifiers

I have seen similar error messages reported about auto_ptr derived classes
in STL containers, but my template class seems to have all the required
methods. 

The code below compiles and runs fine with VC++ and BC++ (Kylix3/Suse8.0). I
would greatly appreciate any help that you can offer.

Regards,

Frits

===== main file ===========================================================
#include <stdio.h>
#include <vector>

template <class T> class SmartPtr
{
private:
	T* m_pI;
public:

    SmartPtr(T* p = NULL) 
	{
		m_pI = p;
		if (m_pI != NULL)
			m_pI->AddRef();
	}

    ~SmartPtr()
	{
		if (m_pI != NULL)
		{
			T* old = m_pI;
			m_pI = NULL;
			old->Release();
		}
	}

    SmartPtr(const SmartPtr& r) throw() 
	{
		m_pI = r.m_pI;
		if (m_pI != NULL)
			m_pI->AddRef();
	}

    SmartPtr& operator=(const SmartPtr& lp)
    {
		if (m_pI != lp.m_pI)
		{			
			T* pOld = m_pI ;    
			m_pI = lp.m_pI ;    
			if (m_pI != NULL)
			{
				m_pI->AddRef() ;
			}
			if (pOld != NULL)
			{
				pOld->Release() ;       
			}
		}
        return *this;
    }

    T* operator->() { return m_pI; }
	T** operator&() { return &m_pI ;}
    T& operator*()  { return *m_pI; }
	operator T*() { return m_pI ;}

};

class CX {
public:
	CX() { printf("CX::CX()\n"); cnt = 0; }
	~CX() { printf("CX::~CX()\n"); }
	void AddRef() { ++cnt; }
	void Release() { --cnt; if (cnt==0) delete this; }
private:
	long cnt;
};

typedef SmartPtr<CX> XPtr;

int main()
{
	CX* px = new CX();
	XPtr sp(px);
	std::vector<XPtr> v;
	v.push_back(sp);  // THIS IS THE LINE THAT OFFENDS G++
	return 0;
}


F.K. van Evert
Plant Research International
Phone (+31) 317-475957, Fax -423110