[Boost-users] Connecting signals where one is a member

Hello, "Connect 4" fails to compile in the code below on g++ 4.6.3. Why does "Connect 4" not work while "Connect 2" does work? Connect 4 and 2 are the same thing as far as I can see. Thank you, Chris #include typedef boost::signals2::signal TDSignalA; typedef boost::signals2::signal TDSignalB; TDSignalA SignalA1; TDSignalB SignalB1; struct TSItem { TDSignalA SignalA2; TDSignalB SignalB2; }; int main() { TSItem Item; // Connect 1 SignalA1.connect(Item.SignalA2); // Connect 2 SignalA1.connect(TDSignalA::slot_type(&TSItem::SignalA2, &Item)); // Connect 3 SignalB1.connect(Item.SignalB2); // Connect 4 //SignalB1.connect(TDSignalB::slot_type(&TSItem::SignalB2, &Item, _1)); return 0; }