japanese/mh: Fix APOP authentication breakage

PR: 277664
Reported by: Shigeharu TAKENO <shige@iee.niit.ac.jp>
Approved by: WATANABE Kazuhiro <CQG00620@nifty.ne.jp> (maintainer)
MFH: 2024Q3

(cherry picked from commit ab71398319d2b363cc2a89d5fe7b717a0604f31d)