Bukkit

Bugfixes have come a long way from now, so this is a important update as well and recommend that you update.

Also, AntiBot API!

This not only includes Chat Spam false positives with Commands, this includes a permissions related bugfix as well that's lingered from the past.

• Added The official AntiBot API!, I will have a documentation for this later on. There's also going to be a javadocs as well.
• The Time Consistency check in Chat Spam check, has been given some new tricks. This means chat spammers who like to spam at a constant rate will now get detected.
• Added ability to disable idle checks on CAPTCHA.
• Made improvements to Chat Flow and Chat Spam. Chat Flow now by default (if you disable Captcha or disable the trigger), will kick the offending players when Chat Flow is triggered. Also, Chat Spam's violation levels no longer rise quickly, fixing possible false positives.
• Disabled Delayed Start by default. If you would like this feature, enable it in your configuration. This should make AntiBot fire up as soon as the server starts. If you install this problem and notice that Delayed Start is still enabled, disable it in your configuration.
• antibot.admin now behaves properly, it used to be that antibot.admin only allowed level 3 permissions, but not below. This could've been fixed by giving antibot.admin.basic as well as antibot.admin, but I thought it was too redundant.

There could be times where the plugin may not help you in a spam attack.

The bot kick handling might kick innocents if AntiBot gets triggered as soon as the innocent player joins, or is the last player that triggers AntiBot.