I run a NSFW chan, and I did find that I wanted to completely avoid cp, spam and unwanted posts, so I asked for the current group that keeps Kusaba X up to date with patches and occasionally new releases to write me a Mod that would allow me (Admin or Moderator) to screen all incoming posts before they show up on my site.
They did make it for me and here is the patch/mod the version of it that I prefer http://pastebin.com/1rf4Zw13
And there is a version 3 posted in this thread - http://kusabax.cultnet.net/sup/res/39019.html
. (Note it only works for Kusaba X and possibly anonsaba, but will not work for Tinyboard or other scripts not based on kusaba).
I recommend it to anyone having problems with CP and SPAM or if they are just lazy moderators.
As far as the legality of Jailbait. Let me quote the APA (American Psychiatric association) that attraction to girls aged 14 (and up) is not pedophilia (or a crime).
I moderate my Jailbait board well (probably unlike many others listed on Topchan) and do not allow any nudity or pics that I believe to be of persons under the age of 14.
There are many perfectly legal sites on the internet dedicated to Jailbait that operate professionally (as I do). They are not illegal simply because they use the term 'Jailbait'.
So please lets move away from the aspect of Jailbait somehow being illegal, it's how you moderate it (or don't) that can be illegal (ie nude Jailbait).