We have the problem if we start a jsf action eg using a a4j actionListener call to the backend and a reRender of some component that last more than 40 seconds that (a 'Please Wait' Layer will be displayed until the ajax request usually returns) that the ajax request never returns.
We can see that the backend finishes fine, only the ajax request never returns. It seems that some firewall (which we don't have under control) just terminates the connection, probably seeing that nothing has been transfered over the A4j request for a while. Therefore the 'Please Wait layer' never disappears.
My question is, is there a way to send keep alive messages over the same Ajax connection, with no action associated, just to make the connection not terminate until the backend finishes?
I know other solutions may include polling and so on, but the above one may be the cleanest one.