diff --git a/include/boost/python/init.hpp b/include/boost/python/init.hpp
index c931d701..03625a1b 100644
--- a/include/boost/python/init.hpp
+++ b/include/boost/python/init.hpp
@@ -262,7 +262,7 @@ namespace detail {
     struct count_optionals2 {
 
         BOOST_STATIC_CONSTANT(
-            int, value = boost::mpl::size<typename T::sequence>::value);
+            int, value = boost::mpl::size<typename T::sequence>::value + 1);
     };
 
     template <class T>
@@ -407,9 +407,8 @@ template <class ClassT, class CallPoliciesT, class InitT>
 void
 define_init(ClassT& cl, InitT const& i, CallPoliciesT const& policies, char const* doc)
 {
-    enum { n_defaults_plus_1 = InitT::n_defaults + 1 };
     typedef typename InitT::sequence args_t;
-    detail::define_class_init_helper<n_defaults_plus_1>::apply(cl, policies, args_t(), doc);
+    detail::define_class_init_helper<InitT::n_defaults>::apply(cl, policies, args_t(), doc);
 }
 
 }} // namespace boost::python
diff --git a/test/defaults.cpp b/test/defaults.cpp
index b6d2a72f..0f552666 100644
--- a/test/defaults.cpp
+++ b/test/defaults.cpp
@@ -91,6 +91,10 @@ struct X {
     : state(format % make_tuple(a, b, c, d))
     {}
 
+    X(std::string s, bool b)
+    : state("Got exactly two arguments from constructor: string(%s); bool(%s); " % make_tuple(s, b))
+    {}
+
     object
     bar(int a, char b = 'D', std::string c = "default", double d = 0.0) const
     {
@@ -162,11 +166,13 @@ BOOST_PYTHON_MODULE_INIT(defaults_ext)
 
 # if (!defined(BOOST_INTEL_CXX_VERSION) || BOOST_INTEL_CXX_VERSION > 600)
         .def(init<int, optional<char, std::string, double> >())
+        .def(init<std::string, bool>())
 # else
         .def_init(args<int>())
         .def_init(args<int, char>())
         .def_init(args<int, char, std::string>())
         .def_init(args<int, char, std::string, double>())
+        .def_init(args<std::string, bool>())
 # endif
         .def("get_state", &X::get_state)
         .def("bar", &X::bar, X_bar_stubs())
diff --git a/test/defaults.py b/test/defaults.py
index 701ba386..aa7602f2 100644
--- a/test/defaults.py
+++ b/test/defaults.py
@@ -66,6 +66,9 @@
 'int(1); char(K); string(Kim); double(0.0); '
 >>> x.bar2(1, 'K', "Kim", 9.9).get_state()
 'int(1); char(K); string(Kim); double(9.9); '
+>>> x = X("Phoenix", 1)
+>>> x.get_state()
+'Got exactly two arguments from constructor: string(Phoenix); bool(1); '
 
 """
 def run(args = None):