I'd be happy to send you an invite to join google mail aka gmail, Dave, but you'd have to PM me a working addy.

Have you checked your settings in FireFox under Tools - Options? I had some kind of problem like that with Yahoo, too, about a year ago, I think it was. Can't remember what I did, except I think I had to set it to accept all cookies, then erased them all after each session. Eventually it understood I'd accept cookies from only certain sites to which I added Yahoo and it sorted itself out. Sorry that's probably not much help.:-)