authentication in spring security case insensitive

i found that in my app the security with spring security does not check the case of my usernames at loging.

I have this code:

        authBuilder
                .jdbcAuthentication()
                .dataSource(dataSource)
                .usersByUsernameQuery("SELECT username, password, enabled FROM Utenti WHERE username = ?")
                .authoritiesByUsernameQuery("SELECT username, role FROM Utenti WHERE username = ?");

I dont know why when i use different particular cases for the username, the authentication of spring permits all. Can someone help me?

Thanks