It was a long time ago I made scripts. This code works great for me.
The code could take longer times in channels that have many users.
If someone else could come up with a better way, that would be nice.

Code
on 1:INPUT:#:*:{
  var %totalNicks = $nick($chan,0)
  %inc = 1
  while(%inc < %totalNicks) {
    if ($nick($chan,%inc) == $1) {
      say $+($1,:,$chr(32)) $2-
      haltdef
    }
    inc %inc
  }
}