I'm seeing an inexplicable failure in xpressive on HP Tru64. My highly scientific approach of randomly changing stuff and hoping for the best hasn't panned out. Is there anybody with this compiler who would like to help out tracking down this bug: <http://tinyurl.com/3e3low>? Just try compiling the following program: #include <iostream> #include <boost/xpressive/xpressive.hpp> using namespace boost; using namespace xpressive; int main() { sregex rex = +_w; std::string str("foo bar baz"); std::string fmt("\\u$&"); str = regex_replace(str, rex, fmt, regex_constants::format_perl); std::cout << "Expected : Foo Bar Baz" << std::endl; std::cout << "Actual : " << str << std::endl; return 0; } Based on the test failure, I'm guessing the actual output will be: Expected : Foo Bar Baz Actual : FOO BAR BAZ If that's the case, I'll be asking you to fire up a debugger. I can tell you exactly where to look, but only you can tell me what you'll find! -- Eric Niebler Boost Consulting www.boost-consulting.com