Another technique, which I've used with great success on modern browsers, is to have a hidden floating div with the 'please wait' message. Just before submitting the form, cause the div to display. It hangs around until the browser is ready to start painting the response.
I am not sure if you can create a thread from within a servlet.
If it is possible
create a status servlet which a) looks for the status in the db or a singleton class. b) starts the actual working process.
Things get always more complicated as expected.<br />Author of eBook Hibernate 3 Developer Guide by example<br />Tutorials about Hibernate, EJB, Struts, JSF <a href="http://www.laliluna.de" target="_blank" rel="nofollow">www.laliluna.de</a>
Joined: Jul 22, 2004