AutoCAD .NET :: Get ActiveLayout Object In 64bit OS?

Has run into this problem with AutoCAD 2012, where you can't get the ActiveLayout.Name property from a Windows 64bit OS? This code only seems to work in 32bit OS. Any other way to get ActiveLayout in 64bit?

In this example code,using the following namespace:

namespace Autodesk.AutoCAD

Code example, but does not work in 64bit OS:

AcadDocument acadDOC = (AcadDocument)(openedSheet.AcadDocument); 
if (acadDOC != null) 
layoutName = acadDOC.ActiveLayout.Name;