Acdbmgd versions compatibility issues

In one my codes I am using a property of an Editor [ ActiveViewportId ] and I am able to compile that when I reference the (acdbmgd, acmgd) from 2011 without any problems.

When I try to do the same for the 2008, I get an error stating that [ ‘ActiveViewportId’ is not a member of ‘Autodesk.AutoCAD.EditorInput.Editor’ ]

Do we as .net programmers have a remedy for situations like the one above? Can we import objects from one class library to another? I am just trying to find the best way on how someone would go about trying to make their code compatible across several versions of AutoCAD.

Thank you,

-J

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