Hi, I am trying to use boost.python 1.28 with gcc 3.1 on cygwin, and I am getting an error that puzzles me: $ gcc -c -I/usr/src/boost_1_28_0 -I"/e/Program Files/Python/include" -I/home/nickm/sources/include -I/e/ug150/ugopen -mno-cygwin -shared /home/nickm/sources/src/ugx/py/styler_py.cpp -o styler_py.o /usr/src/boost_1_28_0/boost/python/cross_module.hpp: In instantiation of `boost::python::python_import_extension_class_converters<std::vector<tag_t, std::allocator<tag_t> > > boost::python::py_extension_class_converters(boost::python::type<std::vector<tag_t, std::allocator<tag_t> > >, bool)': /usr/src/boost_1_28_0/boost/python/detail/extension_class.hpp:388: instantiated from `PyObject* boost::python::to_python(const T&) [with T = std::vector<tag_t, std::allocator<tag_t> >]' /usr/src/boost_1_28_0/boost/python/callback.hpp:70: instantiated from `static R boost::python::callback<R>::call_method(PyObject*, const char*, const A1&, const A2&) [with A1 = std::vector<tag_t, std::allocator<tag_t> >, A2 = saUIStyler::DialogSelection, R = saUIStyler::CallbackResult]' /home/nickm/sources/src/ugx/py/styler_py.cpp:225: instantiated from here /usr/src/boost_1_28_0/boost/python/cross_module.hpp:71: default argument given for parameter 2 of ` boost::python::python_import_extension_class_converters<std::vector<tag_t, std::allocator<tag_t> > > boost::python::py_extension_class_converters(boost::python::type<std::vector<tag_t, std::allocator<tag_t> > >, bool = 0)' /usr/src/boost_1_28_0/boost/python/cross_module.hpp:71: after previous specification in ` boost::python::python_import_extension_class_converters<std::vector<tag_t, std::allocator<tag_t> > > boost::python::py_extension_class_converters(boost::python::type<std::vector<tag_t, std::allocator<tag_t> > >, bool = 0)' /usr/src/boost_1_28_0/boost/python/cross_module.hpp: In instantiation of `boost::python::python_import_extension_class_converters<DVect3D> boost::python::py_extension_class_converters(boost::python::type<DVect3D>, bool)': /usr/src/boost_1_28_0/boost/python/detail/extension_class.hpp:388: instantiated from `PyObject* boost::python::to_python(const T&) [with T = Vector3D<double>]' /usr/src/boost_1_28_0/boost/python/callback.hpp:125: instantiated from `static R boost::python::callback<R>::call_method(PyObject*, const char*, const A1&, const A2&, const A3&, const A4&) [with A1 = tag_t, A2 = Vector3D<double>, A3 = Vector3D<double>, A4 = saUIStyler::DialogSelection, R = saUIStyler::CallbackResult]' /home/nickm/sources/src/ugx/py/styler_py.cpp:265: instantiated from here /usr/src/boost_1_28_0/boost/python/cross_module.hpp:71: default argument given for parameter 2 of ` boost::python::python_import_extension_class_converters<DVect3D> boost::python::py_extension_class_converters(boost::python::type<DVect3D>, bool = 0)' /usr/src/boost_1_28_0/boost/python/cross_module.hpp:71: after previous specification in ` boost::python::python_import_extension_class_converters<DVect3D> boost::python::py_extension_class_converters(boost::python::type<DVect3D>, bool = 0)' Can somebody help me understand what the problem is? Thanks in advance Nikolay