That's bizarre. I use firefox under both windows and linux, and I haven't noticed what you mention. I'll watch for it though. What version of Firefox are you running? I have 1.5.0.7 under Linux, and 1.5.0.8 (Ooops,.. just upgraded this minute to 1.5.0.9) under windows. You're not using the new V2 are you?
I know that Pete must have done a board upgrade at some point, because our quoting stuff is fixed, perhaps the new version has the bugs that you mention under specific circumstances... ?