msgfmt: ??????? 23 ??????????? ??????
../../ru/LC_MESSAGES/frontend.po:725: number of format specifications in 'msgid_plural' and 'msgstr[0]' does not match
../../ru/LC_MESSAGES/frontend.po:733: number of format specifications in 'msgid_plural' and 'msgstr[0]' does not match

#: include/maintenances.inc.php:63
#, c-format
msgid "At %1$s:%2$s on every day"
msgid_plural "At %1$s:%2$s on every %3$s days"
msgstr[0] "? %1$s:%2$s ?????? ????"
msgstr[1] "? %1$s:%2$s ?????? %3$s ???"
msgstr[2] "? %1$s:%2$s ?????? %3$s ????"

There is some doc for these languages: http://www.gnu.org/software/gettext/manual/html_node/Translating-plural-forms.html