ban on user account

[CrazyEgg]

i understand that ban on ip meaning the user even login cannot join a channel.

can be and invers possible?
what mean with that:
nickname is ident@account.users.undernet.org
if i ban the user then he just connect a clone unregister and join in chan.
If i ban AND ip then reset modem and recconect with other ip.Too many bans for one user(mostly kids)

a good idea is if a user account is ban then automaticaly even and with ip cannot join a channel.
X keep log useraccount = ip. Then if useraccount is ban then even ip cannot join the room where is banned.
P.S not 2 bans ONLY refuse join or kick out the clone.
Specification:useraccount is ban for 100 h for example means that with any ip connected cannot join the channel where is ban.Require user being login.IF first join and after login then x imediatly kick out the nick.

exact invers with the ban ip = kick out and register user under that ip or domain.

Thanks