Tunnel Interfaces (PPTP) and QOS

I have a simple network, not many users in it, and have some queue tree to share the bandwidth. It works fine actually, pretty satisfied.
Mean while, I do have also a remote location which connects to the same router via wireless. Some devices on the remote site are connected to the router using PPTP tunnel so that they do not do double nat. The problem is that the pptp interfaces do not pass through the queue tree rules. I have attached the download queue on the ether2 interface which is the local interface and where the pptp clients actually connect.
Is there any way to have these pptp interfaces encapsulated under ether2 interface? Or is there any other tunnel protocol which would create the interfaces under the physical interface at which it connects?

Thank you.