[boost] status of wchar_t support in filesystem::path?

I just started using boost recently and it seems excellent so far. One of the first classes I started using is filesystem::path, with the intention to use it portably on Windows, OS X, and Linux. On Windows and OS X, you can work with paths in Unicode. Presumably Linux still works with multi-byte characters. Is there progres toward a wchar_t-aware path? Is there an existing strategy for storing my Unicode Windows/Mac paths as UTF-8 with the existing path? I notice the existing posix checks would fail horribly in this case. Is a UTF-8 checker in order?