Australian users please take note! If you currently use Twitter via your mobile device instead of over IM or the Web we have some news. Right now, Twittering via sms in Australia is more expensive than it needs to be—for you and for us. Our short term solution is to suspend sms support for Australian users.
When sms support for Australia returns it will be better all around. We'll let you know as soon as it does. In the meantime, we recommend using Twitter over IM, Web, Twitterrific, or any of these interesting alternatives.