I'm having some trouble when borrowing a license for AutoCAD and Revit of different versions.

I was expecting to use Revit 2009 and AutoCAD 2011 on a laptop so I checked out a license for Revit 2009 which does work for AutoCAD 2011. If I check out the license in AutoCAD 2011 then Revit 2009 does not see the license as borrowed when I'm offline. I can go ahead and checkout for both AutoCAD 2011 and Revit 2009 but now that counts as (2) licenses borrowed from the same computer. Is that how the AutoDesk licensing works.. by version? I thought I could go back three versions and use anyone of them?

I've tried adding the license manager file information into an environmental variable which should then show the license as "Distributed" but that doesn't seem to work either.

Am I doing something wrong or is it just not how the license manger works? 1 license per version used?