It's probably been close to a year, or a bit more than that, since I gave up on the Photobucket java bulk uploader. Back then, the applet worked in Windows but photobucket didn't care enough to make it work on Linux (there were forum posts about how it didn't work on non-Windows boxes).
I did upload some files from either my wife's windows partition (which we keep for legacy devices that work only in Windows, e.g., a Sony NW-HD1 that was given to us and that doesn't seem to have any linux support at all). I remember using windows under vmware to test the bulk uploader too.
I recently upgraded to Ubuntu 8.10 (Intrepid) and I'm glad to report that the bulk uploader now works with the Sun Java 1.6 JVM. I don't have 1.5 installed just now, so I don't know if it'll work with that. But I'm glad that I've finally got a working setup.