Doorkeeper will be undergoing a scheduled system maintenance on Saturday, May 25th 2013, 11pm - 12pm JST (what time is that for you?). During this period, Doorkeeper will not be reachable for some time. This maintenance is required by our hosting provider and we will also use this maintenance window to perform some upgrades.
We do hope the actual downtime will be less than the stated one hour. Please follow @doorkeeper_app on Twitter for real time updates during the maintenance.
Thank you for your patience!