In Omerta IRC we have a bot that consistently scans ips of new users in order to find blacklisted or "bad users" and bans them, yesterday (26 December 2014) one of the services that provides us the blacklists was discontinued: Ahbl.
You can read more about it in here: http://www.ahbl.org/content/changes-ahbl & http://www.ahbl.org/content/last-notice-wildcarding-services-jan-1st
The way they decided to stop the service was to force every scan to show as blacklisted, this caused the issues with our network, every new connection got banned and only the ones that never disconnected IRC could stay.
The situation is now FIXED.
Meanwhile, we will update this post to inform when our bot Helpster is back, as he was the bad guy banning everyone we just plugged it off.
Update #1: Helpster is back online.