I already wrote it to the Users-Mailinglist, but maybe not all are signed in there, so I write it here again.
I fixed the problem of the community-page not being able to send mails, which prevented new users from creating accounts and old users to request a new password because the mails didn't get to them.
So if you registered an account but never received the password-mail, just go to
Request new password and request a new one. And of course the same if you forgot your password and need a new one, even if you already tried it and didn't receive a mail. NOW it should send you the requested mail.