We require two java applets which will work in IE 6/7 on Windows, Firefox 1.5/2.0 PC, Firefox Mac, and Safari (OSX Tiger).
The second applet must submit (PUT) these three files to a DAV server (no POST) for reassembly on the server. This applet must display only a progress indicator. On failure, the applet must get HEAD, read bytes completed and resume upload. On success, applet must redirect browser to "completion" page.