I want to install my plugins in a single jail. I created a jail called pbis for my plugins. The problem is that it's running a standard jail, so i can't seem to upload any plugins. How do i change that?
You can't. Plugins are point and click and you get what you get (a jail for each plugin). Jails you can customize anyway you want, but you're doing it yourself using ports/pkgs. Take a closer look at http://doc.freenas.org/9.3/freenas_jails.html for an overview of the difference between plugins and jails and instructions for managing software within a jail.