The bug is fixed now an no longer reproducible with the latest Intel C++ Compiler XE 126.96.36.1990 (12.1 Update 9). The sample main.cpp builds fine with Visual Studio 2010. However, on Visual Studio 2008 there is a syntax error now (also occuring with the Microsoft Compiler) which may have to do with missing or unsufficient support in the standard C++ Library TR1 extensions inVisual Studio 2008. I haven't looked deeper into this since the subject here was the bug with the backend signals which is now solved. Please have a try with the latest Intel Compiler. If you need help with the std::tr1::function syntax error under VS2008 you may follow up here. Regards, Hubert.