Limit Multiple Logins from one machine ..not by user - terminal server

Does anybody know of, or have a method, to restrict a Windows 2008 terminal server to a single session per remove workstation or preferably, per remote workstation & user combination.  

I am familar with the options and settings to limit each user to one session but that does not work in my environment.  I need to allow the same user access to the terminal server from multiple machines at the same time, but I need to prohibit them from having multiple sessions open from the same computer.

Any ideas?