App fails to load cocoa platform plugin with some unicode characters

I deploy my OSX application with macdeployqt, the cocoa platform plugin is at the right place. Everything is ok, we have thousands of users, but I received crash reports mostly coming from japanese people, the app crashes in
QGuiApplicationPrivate::createPlatformIntegration

I can reproduce it by just renaming my application package into ⻨.app, or by putting it in a folder named "⻨"

I tested versions built with Qt 5.2, Qt 5.4.1 and Qt 5.5.0, all have the same issue. Old application releases with Qt 4.7.X don't have this issue.