The language switch does not work after upgraded to 6.x-2.3

I am maintaining a Japanese and English site.

I was able to view my site in English and Japanese by clicking the language switch or putting /ja or /en at the URL .
After upgrading the automated logout to 6.x-2.3, I can only view Japanese version with a Japanese browser
(and the English version with an English browser), no matter I click the language switch button (Actually, the URL has changed
to example.com/ja or example.com/en after I clicked the button) the language will not change.
If a user login with Japanese as his default language, he can only view the Japanese version (no matter what language the browser is.
In the same way, if a user login with English as his default language, he can only view the English even in a Japanese browser.

I have unchecked the module (without changing other settings), and the site works fine again. I tried to uninstall it and install the 6.x-2.2 version,
it works fine with 6.x-2.2 too.