I think this is just a firefox 3.0.6 issue with stored passwords.
When you go to your profile it looks like it inserts your browser stored password in the password field then picks up the hashed verify password field. So when you submit the passwords don't match.
Then the stored password in firefox seems to change to something like 123456789123456789 which is not correct.
So if you log out then back in the browser stored password is incorrect.
This does not happen in ie7
