[boost] [Regex] Why doesn't this pattern match?

Hello, can, please, somebody explain, why this code doesn't work? std::wstring str = L"Line \\n line \\n line \\n"; std::wstring result = L""; const boost::u32regex e = boost::make_u32regex(L"\\n"); std::wstring newText = L"\n"; result = boost::u32regex_replace(str, e, newText); After launching result == str... :((( I also tryed with const boost::u32regex e = boost::make_u32regex("\\n"); but result was the same... I am using Regex from bost 1.37.0 compilled with ICU 4.2.1 Visual Studio 2008.