ISP blocked due to abuse?

Well, it seems today that I'm now unable to post anything over at the 4chan imageboards, otherwise I get this message:
"Posting from your ISP has been blocked due to abuse. [More Info]"
I can still browse the site, all the images and threads load fine, I just can't post. What gives? I've never posted spam or porn.

Romania fag here, my ISP (RDS net) is banned too. It sucks to be banned because of other idiots using spambots or posting CP, I hope moot gets raepd