On Friday, September 4th 2009 at 10:00 AM Eastern we will be changing the IP address for our Australia Exchange server due to changes in the network layout in the data center. Before the change we will lower the TTL time on the DNS record (exchange.australia.exchangedefender.com) to minimize the chance of downtime/unavailability.
Users on the Australia server should not have to make any changes after the IP address change for service to continue working.
Update 12:10 PM Eastern: The IP change has been delayed until later today. We will update this post before the change occurs.