Steps To Reproduce :
1. Configure LDAP with Import from LDAP checked
2. Login with an LDAP user and change the language to a different one from the default.
3. Logout and access the portal again with the default language.
4. Login with the previous LDAP user again.
Result: The users language settings are overridden to the default.
Since we don't import languageId from LDAP we should't use the portal default if the user already exists in the portal, but the languageId of the existing user.