I have all of those characters in the "Latin-1 Supplement" in the Unicode popup for text input on my standard Sharp ROM 2.38. Search oesf for information about the "keyhelper" application. I am not sure which ROMs and models it works on, but IIRC it is meant for Cxxxx series. I figure if I have it on my old Sharp ROM, you ought to be able to get it on your newer model.
They don't have input method choices on cacko for C3000? And try keyhelper out. Sorry I don't have exact forum topic # but it should turn up fast in a search...I think subject was about replacing "," with "\", or something like that, for one of the better threads.
sdjf