Instead of using multiple physical ports, you can trunk multiple VLANs on a single port, just like a router-on-a-stick.

Go to your mgmt interface and edit the properties. Uncheck the "Dedicate this interface to management only" and it is treated like a regular interface; If you need more ethernet ports, purchase a 4port eth module for the units containing the expansion slot, or, make subinterfaces off of your existing ethernet interfaces.

Hope this helps?