It was requested on the google groups to share a sample application showing how to make your ajax calls synchronous to enable more predictive testing using JWebUnit. This removes the necessity of using a random Thread.sleep(X) to wait for the ajax call to be done.
Here is the google group thread
git clone git://github.com/briannesbitt/PlaySampleWithJWebUnitWithAjax.git
cd PlaySampleWithJWebUnitWithAjax
play autotest
You can also run play test
and then browse to http://127.0.0.1:9000
to try it or http://127.0.0.1:9000/@tests
to run the tests manually.
Read more on my blog