--- boost/spirit/home/support/attributes.hpp	2010-08-20 11:57:12.000000000 +0200
+++ boost/spirit/home/support/attributes.hpp	2010-08-23 18:53:15.000000000 +0200
@@ -15,6 +15,7 @@
 #include <boost/spirit/home/support/unused.hpp>
 #include <boost/spirit/home/support/has_semantic_action.hpp>
 #include <boost/spirit/home/support/attributes_fwd.hpp>
+#include <boost/spirit/home/support/container.hpp>
 #include <boost/spirit/home/support/detail/hold_any.hpp>
 #include <boost/spirit/home/support/detail/as_variant.hpp>
 #include <boost/optional/optional.hpp>
@@ -900,7 +901,7 @@
     template <typename Out, typename T>
     struct print_attribute_debug<Out, boost::optional<T> >
     {
-        static void call(Out& out, T const& val)
+        static void call(Out& out, boost::optional<T> const& val)
         {
             if (val)
                 print_attribute(out, *val);