This is a simple modification to the Hidden User ( +Dm ) Delay voice (Undernet) by Xpl0reR.
Today's flood bots sometimes stick around to get voiced by the original Dm script. My modification to this script will generate a random code, and request the user return said code to prove that they are human. To use this script, copy it into your remotes section, then right click in a channel and select Delay Voice > On.

Usage Note: This script can only be used in ONE channel at a time.

Security Note: This script is in its infancy, and can still be defeated by those who are determined to do so. This countermeasure is merely a bandaid fix to a larger problem. Also, the operator running this script runs the risk of getting flooded off. It is recommended that you run this script from a client that can hide behind RFC1918 (where possible).

Bug Note: Some users have reported being flooded by the script after idling in a channel without responding to the captcha . If you find any additional bugs or have a solution for this bug (or anything else with this script) please join #krystilynn on undernet, and tell me, or leave your comments here.

Credit Note: I do not take credit for the only script. All I did was merely implement the captcha system, which anyone could've done.

/*
Hidden User Delay Voice System                    
Made To work With +Dm channel Modes On Undernet            
Originally Coded By Salman, on #mircscripting            
Recoded, Tweaked, Adjusted  By xplorer. on #mircscripting
Captcha added by QueenElsa      
For Help /msg QueenElsa on Undernet or join #development
*/

on *:LOAD:{
  echo -at You just loaded The delay voicer Script That works with +Dm channel modes on Undernet
  echo -at This Script Will ONLY work on Undernet Since They have implemented +D
  echo -at Simply Right Click in the channel And Click ''Delay Voice''  
  echo -at 4THIS SCRIPT WILL ONLY WORK IN ONE (1) CHANNEL
  echo -at From: xplorer irc.undernet.org #mircscripting xplorer@live.ca
  echo -at Captcha function added by QueenElsa (krystii.users.undernet.org) #development, #usa, #undernet
  window -ke @DmCAPTCHA
  echo -at [A message from QueenElsa] ** If you need help with this script, join #development.
}

on *:UNLOAD:{
  echo -at What Have you Done ??
  echo -at Fine Then!
  echo -at :p try again later ;)
}

menu channel, {
  $iif(undernet isin $network,Delay Voice)
  ..ON:/husers | mode $chan +Dm
  ..OFF:/husers | mode $chan -Dm
}

alias husers {
  .names -d $chan
  if ( $timer(hUsers) != $null ) {
    .timerhUsers off | unset %huserchan
    echo -at Delay Hidden voice Script is Off!
    unset %dmchan
  }
  else { .timerhUsers 0 15 .names -d $chan | set %huserchan $chan
    echo -at Delay Hidden voice Script is On! Make 4Sure That everyone is +v
    set %dmchan $chan
  }
}

raw 355:*: {
  if ( $4 == $null ) { HALT }
  else {
    set %allnicks $4-
    set %i 1
    :next
    set %nick $gettok(%allnicks,%i, 32)
    if %nick == $null goto done
    if $istok( %nrdone,%nick,32 ) { inc %i | goto next }
    .set -u60 %nrdone %nrdone %nick
    .enable #ghost
    .whois %nick
    .set -u300 %hucheck. [ $+ [ %nick ] ] $rand(A,Z) $+ $rand(1,10) $+ $rand(A,Z) $+ $rand(1,10) $+ $rand(1,10) $+ $rand(1,10) $+ $rand(A,Z) $+ $rand(A,Z) $+ $rand(1,10)
    .msg %nick ATTENTION: You just tried to join %dmchan $+ . Since we're being attacked by bots, please type: %hucheck. [ $+ [ %nick ] ]  to prove that you're a human. If you do, you will be permitted to join. If you mess up, nothing will happen.
    inc %i
    goto next
    :done
  }
  halt
}

raw 366:*: halt

#ghost off
raw 301:*: halt
raw 310:*: halt
raw 311:*: { echo -at 4 $+ Scanning Hidden User: $address($2,5)  | halt }
raw 312:*: halt
raw 313:*: halt
raw 330:*: halt
raw 319:*: halt
raw 317:*: halt
raw 318:*: { .timer 1 5 .disable #ghost | haltdef }
#ghost end

on *:text:*:?:{
  if ($1 = %hucheck. [ $+ [ $nick ] ]) { mode %dmchan +v $nick | msg $nick Welcome to %dmchan $+ , $nick $+ . Sorry for the inconvienence you experienced! | aline @Information 3 $nick ( $+ $addresss($nick,5) has verified that they are human. | halt }
  if ($1 != %hucheck. [ $+ [ $nick ] ]) { halt }
  if (!$1) { halt }
}