Portals

Hey I want to make a cool portal effect in GE, and I need some help. I’ve been trying to get this to work for a while with no results. What I was trying to do is make 2 mirrors and switch them so that it makes a nice portal, can someone help me out?

Search for portals in the resource section, someone made a nice example with portals right around the time render-to-texture was implemented in blender.