In order to get to the manage attachments function, I have to click on paperclip, browse, upload, close window, mark spot in post, click on arrow next to paperclip (this is all fine, but NOW...) then the silly upload window opens AGAIN, then I close it, then I mark the spot in the post again, then I click on the arrow next to the paperclip, then I choose my file, which shows up there now but didn't before. This has been the case for me in Camino, FF, and Chrome.
In 2007 I was told that it's a bug in the forum software. If I'm wrong though and that's no longer the case, someone will probably come along and correct me.