The "long" script you are talking about can be found here:
http://www.erler.org/Olathe/exploit%20fix.mrc

Now if you are a v6-6.03 user and you only want to reject the exploit, simply type /ignore -wd * once and put this line in the remote:
  • On *:notice:dcc & *:?:.ignore -xu10 $nick
That's it. If you are happy with it you can stop reading here.

-

If you are a channel operator who needs to be able to detect the exploiter and kick him, you must get mIRC v6.1+ (where the -i switch of /debug is supported) and put this piece of code in the remote:
  • On *:logon:*:{
    .debug -i nul xploit
    }

    alias xploit {
    if $regex($1,/^<- :[/b](\S+)!\S+@\S+ privmsg (\S+) :\x01dcc (?:send|resume|accept) +\S*"(?:\S* ){35}/i) {
    echo 4 -at > Possible DCC Exploit by $regml(1) on $regml(2)
    }
    }
$regml(1) represents the exploiter's nick, and $regml(2) is the target (you or a channel). Use these identifiers in further commands you may want to add, for example: /ban -k $regml(2) $regml(1) 2 <kick msg>.