Hi all, I have a class like below and I want to declare a signal type inside my class. Unfortunately when I do that MS VC80 complaints. Any help highly will be appreciated. template <typename T> class MyTask { public: // type definitions typedef enum { waiting, running, completed, failed } States; typedef boost::signal StatusChanged; typedef boost::signals::connection Connection; }; I get two warnings first then an error: Warning 1 warning C4512: 'boost::signals::detail::bound_objects_visitor' : assignment operator could not be generated c:\lib\boost\include\boost-1_33\boost\signals\trackable.hpp 185 Warning 2 warning C4346: 'boost::signal::slot_function_type' : dependent name is not a type c:\projects\tesla-at-sti\src\lumentest\devices\nitask.hpp 124 Error 3 error C2061: syntax error : identifier 'slot_function_type' c:\projects\tesla-at-sti\src\lumentest\devices\nitask.hpp 124 if I replace 'States' with an int type then it works. I think compiler can't find out the type of States properly... I've also tried following declarations. None of them worked. typedef boost::signal StatusChanged; typedef boost::signal StatusChanged; typedef boost::signal StatusChanged; thanks, Emre