Index: boost/enable_shared_from_this.hpp
===================================================================
--- boost/enable_shared_from_this.hpp	(revision 44152)
+++ boost/enable_shared_from_this.hpp	(working copy)
@@ -109,6 +109,15 @@
     }
 };
 
+// register enable_shared_from_this<T> as an observer
+template<class T, class Y> void sp_notify_observer( shared_ptr<Y> * ptr, enable_shared_from_this<T> const * pe )
+{
+    if(pe != 0)
+    {
+        pe->_internal_accept_owner(*ptr);
+    }
+}
+
 } // namespace boost
 
 #endif  // #ifndef BOOST_ENABLE_SHARED_FROM_THIS_HPP_INCLUDED
Index: boost/shared_ptr.hpp
===================================================================
--- boost/shared_ptr.hpp	(revision 44152)
+++ boost/shared_ptr.hpp	(working copy)
@@ -50,7 +50,6 @@
 
 template<class T> class shared_ptr;
 template<class T> class weak_ptr;
-template<class T> class enable_shared_from_this;
 
 namespace detail
 {
@@ -93,35 +92,50 @@
 
 struct ignore_enable_shared_from_this_tag {};
 
-template<class T, class Y> void sp_enable_shared_from_this( boost::shared_ptr<Y> * ptr, boost::enable_shared_from_this<T> const * pe )
+
+#if !defined( BOOST_NO_SFINAE ) && !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION ) && !defined( BOOST_NO_AUTO_PTR )
+
+// rvalue auto_ptr support based on a technique by Dave Abrahams
+
+template< class T, class R > struct sp_enable_if_auto_ptr
 {
-    if(pe != 0)
-    {
-        pe->_internal_accept_owner(*ptr);
-    }
-}
+};
 
+template< class T, class R > struct sp_enable_if_auto_ptr< std::auto_ptr< T >, R >
+{
+    typedef R type;
+};
+
+#endif
+
+} // namespace detail
+
 #ifdef _MANAGED
 
 // Avoid C4793, ... causes native code generation
 
+namespace detail
+{
+
 struct sp_any_pointer
 {
     template<class T> sp_any_pointer( T* ) {}
 };
 
-inline void sp_enable_shared_from_this( sp_any_pointer, sp_any_pointer )
+} // namespace detail
+
+inline void sp_notify_observer( detail::sp_any_pointer, detail::sp_any_pointer )
 {
 }
 
 #else // _MANAGED
 
 #ifdef sgi
-// Turn off: the last argument of the varargs function "sp_enable_shared_from_this" is unnamed
+// Turn off: the last argument of the varargs function "sp_notify_observer" is unnamed
 # pragma set woff 3506
 #endif
 
-inline void sp_enable_shared_from_this( ... )
+inline void sp_notify_observer( ... )
 {
 }
 
@@ -131,24 +145,6 @@
 
 #endif // _MANAGED
 
-#if !defined( BOOST_NO_SFINAE ) && !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION ) && !defined( BOOST_NO_AUTO_PTR )
-
-// rvalue auto_ptr support based on a technique by Dave Abrahams
-
-template< class T, class R > struct sp_enable_if_auto_ptr
-{
-};
-
-template< class T, class R > struct sp_enable_if_auto_ptr< std::auto_ptr< T >, R >
-{
-    typedef R type;
-};
-
-#endif
-
-} // namespace detail
-
-
 //
 //  shared_ptr
 //
@@ -178,7 +174,7 @@
     template<class Y>
     explicit shared_ptr( Y * p ): px( p ), pn( p ) // Y must be complete
     {
-        boost::detail::sp_enable_shared_from_this( this, p );
+        sp_notify_observer( this, p );
     }
 
     //
@@ -189,14 +185,14 @@
 
     template<class Y, class D> shared_ptr(Y * p, D d): px(p), pn(p, d)
     {
-        boost::detail::sp_enable_shared_from_this( this, p );
+        sp_notify_observer( this, p );
     }
 
     // As above, but with allocator. A's copy constructor shall not throw.
 
     template<class Y, class D, class A> shared_ptr( Y * p, D d, A a ): px( p ), pn( p, d, a )
     {
-        boost::detail::sp_enable_shared_from_this( this, p );
+        sp_notify_observer( this, p );
     }
 
 //  generated copy constructor, assignment, destructor are fine...
@@ -272,7 +268,7 @@
     {
         Y * tmp = r.get();
         pn = boost::detail::shared_count(r);
-        boost::detail::sp_enable_shared_from_this( this, tmp );
+        sp_notify_observer( this, tmp );
     }
 
 #if !defined( BOOST_NO_SFINAE ) && !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
@@ -282,7 +278,7 @@
     {
         typename Ap::element_type * tmp = r.get();
         pn = boost::detail::shared_count( r );
-        boost::detail::sp_enable_shared_from_this( this, tmp );
+        sp_notify_observer( this, tmp );
     }