I tried to log in using a Unicode username. It does log in successfully, but it displays a big ugly error too:

Internal Server Error
Oops, something went wrong!

Error:

Caught exception in MusicBrainz::Server::Controller::User->do_login "Wide character in syswrite at local/lib/perl5/Redis.pm line 517, line 1."
Stack trace:
line 627 MusicBrainz::Server::Data::Editor
line 205 MusicBrainz::Server::Controller::User
line 109 MusicBrainz::Server::Controller::User
line 143 MusicBrainz::Server::Controller::User
line 324 MusicBrainz::Server
line 298 MusicBrainz::Server
line 325 MusicBrainz::Server
line 339 MusicBrainz::Server
line 384 MusicBrainz::Server
Request data:

$VAR1 = {
'query_parameters' =>

Unknown macro: { 'uri' => '/user/%E3%83%8B%E3%83%83%E3%82%AD%E3%83%BC' }

,
'body_parameters' => {
'password' => 'somepass',
'remember_me' => '1',
'username' => "\x

Unknown macro: {30cb}

\x

Unknown macro: {30c3}

\x

Unknown macro: {30ad}

\x

Unknown macro: {30fc}

"
}
};

Host: astro

URL: http://musicbrainz.org/login?uri=%2Fuser%2F%25E3%2583%258B%25E3%2583%2583%25E3%2582%25AD%25E3%2583%25BC