Trying to use google appengine with the help of Eclipse plugin. I created test application (Google button on the Eclipse toolbar -> New Web Application project), then tried to make some simple changes it to check how it works and encountered a problem. I tried to make something like a simple lottery (user inputs six numbers, then app generates some random sequence of six numbers and user gets the number of matches between his input and result). It works correctly on local server (only in Firefox. Chrome, Opera and Explorer require some gwt plugin. This make me wonder, I thought everything should work without any additional efforts), but after successful deploy at Google cloud when user is sending data to server, he gets this error:
An error occurred while attempting to contact the server. Please check your network connection and try again.
link to my application is da7x-app.appspot.com
I don't think the problem is in code, because on local server application works correctly. Maybe the solution is quite obvious, but I'm newbie and cannot figure it out. I tried to search for problems like mine and their solutions, but haven't found anything, so any help is appreciated.