There seems to be a common problem where the android sdk for versions later than 11 (Honeycomb) are unable to complete the login from your guide - http://developer.authorize.net/integration/fifteenminutes/android/
I may have found a solution, but as this is not something I wrote myself I'm looking for some feedback from people who understand it better than I. Please see my question below.
Mainly the changes to how the ExecuteTransactionTask is run.
I've reported your issue to the product team for analysis.
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