Google calender api with cross domain access error

[Zhang Bruce via StackOverflow]

I'm doing a calendar service app where I call google calendar api from my java servlet which is deployed to app engine.

if I test it with my own google app engine account log in, my app works fine with no problem. However if I use some other google account it gives me cross origin error I wanted to solve it by adding resp.setHeader("Access-Control-Allow-Origin", "*"); to every response I can find, but it just don't work. it will fail at the oauth call.

I also downloaded cors plugin to work around it, but it will get through the oauth only, still wont work for other calls.

Anyone have some ideas?

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