fixed sunpro warnings

src/libCom/cxxTemplates/epicsSingleton.h

@@ -104,8 +104,8 @@ inline epicsSingleton<TYPE>::~epicsSingleton ()
     // sorts of problems then clean up is left to other classes.
 }
 
-// SUN PRO generates warnings unless it sees an implementation
-#ifdef _SUNPRO_CC
+#if defined ( __SUNPRO_CC ) && __SUNPRO_CC <= 0x550
+    // SUN PRO 5.4 generates bogus warnings unless it sees an implementation
     template < class TYPE >
     inline epicsSingleton<TYPE>::epicsSingleton ( const epicsSingleton & )
     {