Thank you for your reply. That makes me feel a little more relaxed, oddly enough. At least I know it's not just me or something I've done.
It is stressing me because I have released a new Kororaa Live CD and people have been email me by the hundreds over the last week, and thus far I've replied to every email. Now I hate to think that people have been emailing me and think I'm ignoring them because I'm never going to reply!
Thanks a lot for letting me know you have the same issue. I just got a reply back from support saying:
"There was a problem w/ the new email system we've devised. It should be fixed now, however, so if you're still having problems, please let us know exactly what info you're using to login, and we'll be happy to look into it for you."
So I have sent them my details in the hope he might actually try it and help fix the problem.
I'm thinking in the mean time I should get them to change my MX record to a system that works. At least then I can get email until they solve whatever issue there is. So if the reply is not positive I'll do just that and then post back here.