Hello, I'm formatting a sink like this: sink->set_formatter ( expr::stream << expr::attr<boost::posix_time::ptime>("TimeStamp") << " T:" << expr::attr<boost::thread::id>("ThreadID") << ":" << expr::smessage ); logging::add_common_attributes(); For some reason ThreadID is empty. I tried to register the attribute explicitly: logging::core::get()->add_global_attribute("ThreadID", logging::attributes::current_thread_id()); but it doesn't help. The program is mutithreaded and linked with mt static libs. Thanks.