You might have noticed that we have currently a spam problem. Over two years it was quiet. But now the bots starts to make it through again. And so we need to take action again.
I am currently at testing several methods to block the spambots. This means that valid registration requests may fail. The page may be unavailable for a while. And the registration method may change until we have found a working method again.
So when you want to register, please wait a few more days until we have a working solution.
I will post a message when we are through with our tests.