UnderNET changed the policy on how operators can be added to the channels with the new version of X (the standard UnderNET bot). Regulars can't be added anymore by the higher ops as they please.
You now have to go to the Cservice homepage. Click on Web Interface to get to the Login page. There you have the option to create a new user.
Do so. Select a unique username and you'll get a password via mail.
Send your username to me and I'll add you to Xs' database.