Create "shadows" above ground only?

[StefanHaglund1]

Hi all,

I have just started poking about the new 3D Features toolset, which seems pretty promising. One of my goals is to generate shadows from buildings, much in the same way as the example in the "Shadow Analysis" tempate here: http://resources.arcgis.com/gallery/file/3D-GIS-Template-Gallery/details?entryID=1C8770F5-1422-2418-...

What I need to do is to have the shadows not go below ground, in other words not to be created below the DEM in the attachment. Another option is to "clip" the shadow multipatches with the ground level after they have been creataed.

Does anyone know if this is possible and how to do it? It doesn't seem like the 3D operators will do it for me and I can't find a setting in the Skyline tools that will create this output.

Thanks!
Nooski