--- a/src/core/ptr.h	Thu May 10 09:57:46 2007 +0200
+++ b/src/core/ptr.h	Thu May 10 18:33:52 2007 +0200
@@ -51,6 +51,7 @@
     void operator delete (void *);
   };
   friend class Ptr<const T>;
+  void Acquire (void) const;
 public:
   /**
    * Create an empty smart pointer
@@ -109,6 +110,13 @@
   template <typename T1, typename T2>
   inline friend bool operator != (T1 const *lhs, Ptr<T2> &rhs);
 
+  // allow if (sp0 == sp1)
+  template <typename T1, typename T2>
+  inline friend bool operator == (Ptr<T1> const &lhs, Ptr<T2> const &rhs);
+  // allow if (sp0 != sp1)
+  template <typename T1, typename T2>
+  inline friend bool operator != (Ptr<T1> const &lhs, Ptr<T2> const &rhs);
+
   template <typename T1, typename T2>
   inline friend Ptr<T1> const_pointer_cast (Ptr<T2> const&p);
 
@@ -116,6 +124,16 @@
 };
 
 template <typename T>
+void 
+Ptr<T>::Acquire (void) const
+{
+  if (m_ptr != 0)
+    {
+      m_ptr->Ref ();
+    }  
+}
+
+template <typename T>
 Ptr<T>::Ptr ()
   : m_ptr (0)
 {}
@@ -123,27 +141,22 @@
 template <typename T>
 Ptr<T>::Ptr (T *ptr) 
   : m_ptr (ptr)
-{}
+{
+  Acquire ();
+}
 
 template <typename T>
 Ptr<T>::Ptr (Ptr const&o) 
-  : m_ptr (o.m_ptr)
+  : m_ptr (o.Peek ())
 {
-  if (m_ptr != 0) 
-    {
-      m_ptr->Ref();
-    }
+  Acquire ();
 }
 template <typename T>
 template <typename U>
 Ptr<T>::Ptr (Ptr<U> const &o)
-  : m_ptr (o.m_ptr)
+  : m_ptr (o.Peek ())
 {
-  if (m_ptr != 0) 
-    {
-      NS_ASSERT (o.m_ptr != 0);
-      m_ptr->Ref();
-    }
+  Acquire ();
 }
 
 template <typename T>
@@ -160,16 +173,15 @@
 Ptr<T>::operator = (Ptr const& o) 
 {
   if (&o == this)
-    return *this;
+    {
+      return *this;
+    }
   if (m_ptr != 0) 
     {
       m_ptr->Unref();
     }
   m_ptr = o.m_ptr;
-  if (m_ptr != 0) 
-    {
-      m_ptr->Ref();
-    }
+  Acquire ();
   return *this;
 }
 
@@ -184,7 +196,7 @@
 T * 
 Ptr<T>::Get () const
 {
-  m_ptr->Ref();
+  Acquire ();
   return m_ptr;
 }
 
@@ -247,6 +259,20 @@
 }
 
 template <typename T1, typename T2>
+bool 
+operator == (Ptr<T1> const &lhs, Ptr<T2> const &rhs)
+{
+  return lhs.Get () == rhs.Get ();
+}
+template <typename T1, typename T2>
+bool 
+operator != (Ptr<T1> const &lhs, Ptr<T2> const &rhs)
+{
+  return lhs.Get () != rhs.Get ();
+}
+
+
+template <typename T1, typename T2>
 Ptr<T1>
 const_pointer_cast (Ptr<T2> const&p)
 {