diff --git a/include/boost/detail/sp_counted_base.hpp b/include/boost/detail/sp_counted_base.hpp
index dee9966..f925a5d 100644
--- a/include/boost/detail/sp_counted_base.hpp
+++ b/include/boost/detail/sp_counted_base.hpp
@@ -39,6 +39,10 @@
 
 # include <boost/detail/sp_counted_base_gcc_ia64.hpp>
 
+#elif defined(__HP_aCC) && defined(__ia64)
+
+# include <boost/detail/sp_counted_base_acc_ia64.hpp>
+
 #elif defined( __MWERKS__ ) && defined( __POWERPC__ )
 
 # include <boost/detail/sp_counted_base_cw_ppc.hpp>