Lightmap is not applied to terrain - Manually apply lightmap?

I am trying to lightmap my scene and I am starting with a single building and terrain. The terrain is 1024x1024 and has different grasses and trees applied to it. I have made sure that 1. the terrain and building are set to lightmap static 2. my directional light has shadows turned on

I do a simple Low quality lightmap test and lightmaps are generated for both my building and terrain. However, when I turn off my directional light and enter Game mode I do not see lightmaps on my terrain (however I do see them on the building). When I return to the Maps tab in the Lightmap dialog, I can see the terrain lightmap however when I rightclick and select "Select LightMap Users" - it DOES NOT select anything in the Hierarchy tab. It's as if it has lost its connection to the terrain. The building lightmaps when selected point to the appropriate building parts in the Hierarchy tab.

This appears to be a bug. I am using Unity 3.5.7f6 on Windows 7. Is there a method for reapplying a lightmap to a terrain?

Thanks in advance for any suggestioos.