[boost] [thread] boost::this_thread::sleep broken?

From the docs I'd expect to be able to write this: std::cout << "Time Before Sleep: " << boost::posix_time::microsec_clock::local_time() << std::endl; boost::this_thread::sleep( boost::posix_time::seconds(10) ); std::cout << "Time After Sleep : " << boost::posix_time::microsec_clock::local_time() << std::endl; and have the 'this' thread sleep for approximately 10 seconds. Instead sleep returns instantaneously: Time Before Sleep: 2010-Dec-25 01:38:50.949160000 Time After Sleep : 2010-Dec-25 01:38:50.949436000 I've tried this with boost 1.45 and boost 1.43 using gcc 4.4 on debian x86_64. Am I missing something obvious? Jamie