script needed to reg nicks & ips

[tom_cruise4g]

hi,

i am a newbee to scripting, so require some help from thy scripters

Act i host a hub locally where at any given time there are 30 users.
these days we are facing prob as the users continiosly change their nicks. so resuming the download from them becomes a prob for other users.(i had tried registering users manually but at last it all get F***ed up)
so i reqest a script from thy lords which can do the foll things
1> when a user joins a hub witha nick name "ass" the script will register the nick name "ass" & his ip add
2> next time if the same user with the same ip join the hub with diffrent nick, he gets kicked off from the hub with the reason" u had changed ur nick, plz change ur nick to "ass" to join.

Hope i was clear with the prob
waiting for sollution
s this posible plz repply ???