Threads Tapestry 5.3.8 vs 5.4.3

I’ve got an issue with threads in tapesty.

I have application that is using tapestry. When I updated from 5.3.8 to 5.4.3 I’ve found that my ajax request are not handled in separate thread.

For example: I have a long process that was executed in controller/class. However, I’ve got also a JS script that is generating ajax request for a component. In Tapestry 5.3.8 those request were handeled normaly. When I switch to 5.4.3 my request are not handeled, unitl my main process from controller ends.

Does anyone know something regarding this behaviour?