Hello, I have my mt working as PPPoE Server, so it uses the global-in global out and global total for my clients bandwith. I want to limit the total bandith so I should use the physic interfaces (eth2 and eth3), but eth3 doesn´t work in my queue tree because the pppoe virtual interfaces are created, so how can I do???

Either in usermanager or MT itself you can set RX/TX limits there. When the client pppoe interface is created in MT a simple queue is added with the values RX/TX you have specified.