http://bugs.winehq.org/show_bug.cgi?id=29038
--- Comment #2 from ZyX kp-pav@yandex.ru 2011-11-10 07:46:50 CST --- (In reply to comment #1)
Confirming. strftime() in msvcrt is just a forward to libc while it probably should be implemented using win32 API GetDateFormat().
It can be a forward to anything, but libc outputs in encoding specified in $LC_TIME, and wine should decode it to expected encoding.
Thanks for the pointer though: if I add `local -x LC_TIME=ru_RU.CP1251' to function that calls vim, tests are passing normally.