Please note that I'm replying to JimmyJump, NOT to Torq.
This problem is not limited to FireFox. I'm using Safari 1.3.2, and for me it additionaly affects my ability to respond to other posters' reviews. Clearing cookies (at Torq's suggestion) worked for me, but everytime I leave the site and return I need to clear again. Since this makes it tedious to navigate to/from/within any other site, I've simply given up on responding to reviews, which is unfortunate.
Am I correct in remembering that FireFox and Safari share a common origin?