As of Gromox 1.33, only HTTP Basic authentication is offered. We have a patch
that makes Gromox send the WWW-Authentication header with the
parameter (RFC 7617 §2.1), however, the MSRPC libraries ignore this. We
recognize there are two bugs with Windows:
When entering a password with an umlaut, the copy of Windows we used transmits in local codepage, but nowhere does it indicate the codepage in the HTTP request. This is a serious design deficiency, especially considering the MAPI protocols themselves do have a means to convey the corresponding codepage number when transmitting 8-bit MAPI property string values! The HTTP requests are also sent with ample custom headers in general.)
When entering a password with a CJK character, the copy of Windows we used does not transmit any Authorization header at all.