Do you mean that a4j:poll that performs the periodical calls does not help to keep the session alive?
Even if the ajax request is sent to the server every 2 seconds using a4:poll, after 30 minutes i.e after the the timeout, i get a pop up "This page contains both secure and non-secre items do you want to display". When i click on yes or no, i get that the Active page is expired.But the main process is running in the background.
So i am not sure whether the a4j:poll is keeping the session alive.
This is the first time I am using a4j:poll.
Weirdly, it does seem so. Is it possible that it can happen?