That's tough. I believe there are commercial tools available that help in this, but they don't (and probably can't) do a perfect job - lots of manual rework is required.
The easiest way to put the app on the web is probably to change it from a standalone application to an applet or a Java Web Start application. Or does it have to be a proper web app based on HTML? [ June 03, 2008: Message edited by: Ulf Dittmer ]