This plugin prevents bots to spam your ticket system. It utilizes Googles reCaptcha. In case a user who is not logged in wants to submit a new ticket, from now on he has to verify he is not a bot.
If you want to use this plugin, you will need to add a security- and site-key which you obtain from Google:
For this reason, the plugin adds a settings box in the Email-Settings of the Support Tickets settings page.
This plugin is licensed unter the GPL. You can download it for free.