I'm going to make a really wierd assumption here..... that most people that are having problems with their FF3 and Flash 10.x are ALSO RUNNING GOOGLE TOOLBAR!
I just did a test by running FF3 in safe-mode and disabling all add-ons and resetting Firefox to factory defaults and after re-enabling all my add-ons I found that the google toolbar was hosing up Flash.
I am currently running Flash 10.15.x and FF 3.06 (Under Suse Linux) and I can now run web presence, IM, and all the other Flash files that come with Dolphin/Ray.
If I'm right everyone has been looking in the wrong direction.
Let me know if this works for you....
