It's kind of humorous you guys ended up here with that question. The error message is related to the service that 'app' was written on, and not an error with the App itself. It should clear up on it's own.
The person who wrote the 'app' shouldn't be passing that message on to end users, as it's obviously confusing. You should be directing your questions to the creator of the App, not Google. They didn't make the app. Obviously the error says to come here though. -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to google-appengine@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.