i have changed unrealircd so that the word netadmin isn't in it at all.
.. and it says the missing operclass is netadmin.
My oper block currently is:
told you, not to edit the operclass default, see if its okay, but you still do it.
also.. if you would paste all your relevant configs and the exact errors from the log, it would be helpful i guess, but i just think, that you changing the files so it causes problems.