Hello! Welcome to this utterly simple (and ugly) page.
A DNL-blocklist (rdnsbl) is hosted here, named dnsbl.beetjevreemd.nl.
If you suspect you are listed, use a regular resolver to find out. Don't forget to reverse the ip! :)
If you are listed, tough luck. Try to find a contact method using tools like whois and nslookup. Probably an abuse-at address works.
Some considerations about this BL. Yes, you may use it. Bear in mind, this was created for personal usage. Nevertheless, it has a good ratio.
Every listing is a manual one. It will never be done on a single message.
Sometimes whole IP ranges are listed, but please be reassured that contact has been sought with the right abuse@ parties.
Because of this, I tend to keep evidence as of why a listing exists (but as a human, I made a mistake or two).
Recommendation: Use this list as a scoring system in your spam-fighting software (such as spamassassin).
I am planning on a double list. One for scoring (or soft bounce) and one for an outright ban. Maybee three.