As mentioned in this kb article, it is not possible to shadow a session with multiple monitors enabled.
It does mention that
Remote Assistance supports multiple monitors, and is the presently recommended solution if you need this functionality.
My question is, is it possible (and if so, how) to remote assist a terminal services session?
We have a few Windows Server 2008 R2 Terminal Servers running with about 10 or so users that use 2 monitors. It would be ideal to be able to remote into their session but have yet to find a viable solution.