I was going to give you guys the link to the OLD uploader (that I have been using forever) but it's not working for me now, nothing will 'link' back to it or I would post it.
I have Vista and use Firefox and have updated Java a million and one times and I STILL have to bypass 2 security screens to use the new uploader. I think IE 8 might have something to do with it on your end...keep filing support requests.
Maybe Mike can post a working link to the OLD uploader in the meantime???