In Collaborator Server 12.4.12402, are there character restrictions for the password ?

Hello

I installed ccollab_server_12_4_12402_windows_x64.exe for testing 

I selected Internal authentication (see attached file)

When created my account in the first screen, I selected a password containing  German regional characters ä ö ü by switching the keyboard layout with Alt+Shift

Now I cannot login in the browser (see attached file and the error from the tomcat\collab.log file)

Are there any restrictions to not use regional characters in the password  ?

If there are restrictions, where exactly it is written in the documentation ?