Bug was encountered during implementation test for CORE5904.
After discuss with Alex it was decided to create separate ticket for this.
After launch cmd.exe and change there code page from OEM to ANSI (1251 in my case) i run following script:
set echo on;
set names win1251;
shell del C:\\MIX\\firebird\\QA\\fbt\-repo\\tmp\\c5904\-w1251\.fdb 2\>nul;
create database 'localhost:C:\\MIX\\firebird\\QA\\fbt\-repo\\tmp\\c5904\-w1251\.fdb' user sysdba password 'masterkey';
create or alter mapping foo using plugin win\_sspi from user 'org\\фуу' to user "org\\foo";
-- and get:
Statement failed, SQLSTATE = 22000
unsuccessful metadata update
\-CREATE OR ALTER MAPPING FOO failed