This looks like a list operated by TDC, a Danish telecommunications opeartor. There is not much information about the inner works of the list but you can get listed by being an open relay, sending viruses, sending too much email, too fast, bad SMTP settings, etc. The whole list is on their website. To get delisted just send an email to them explaning the situation.
Is the information on our site wrong or incomplete? You don't want us to monitor your blacklist? Or do you operate a similar blacklist? We would like to hear from you!