Ajax is usually used to save the time in reloading the whole page.so when you want to use webservices with ajax,what you can do is on some javascript event in the form call the servlet (check w3school) to use ajax, and in the servlet you can make a call to webservice and get the result and return it back to the form.
Regards, sasank.
If I'd had more time, I would have written a shorter letter. -T.S. Eliot such a short, tiny ad:
Gift giving made easy with the permaculture playing cards