I am using Tiki v1.9 RC3. It appears that if I select too many (>~15) available languages in Admin->Login, the user preferences page no longer loads. I did some digging and found that the value of the 'available_languages' preference in the tiki_preferences table was more than the alotted 250 characters. Since the string was being cut short, the unserialize method on line 302 of tiki-user_preferences.php was throwing an error.
For my purposes, there is no real need to have more than 15 languages available to users, but this seems like something that should be fixed.
Does anyone know if this is actually a bug, or if I just missed something obvious in my configuration?