There's an issue regarding the SSL certificate and appspot domain for version of an app, like https://version1.app-id.appspot.com. Seems like Google updated the certificate, but not working for the sub domain like version1.app-id.appspot.com.
This issue just started today. It worked perfectly a few hours ago. -- 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.