According to this blog, this is a problem that started with iOS 5: JavaScript code on the background tabs is paused.
So, when you click "Login" and go to the second page, the first one has no way to return you, because the code is paused.
I tried putting the request in an iframe (to avoid this problem) using the place () method in IN.UI, but was unsuccessful.
You can confirm that this worked in older versions - I tried it on iPod Touch running iOS 4, and it works fine .: '(
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