Interior Lighting in Blender!

[Dread_]

Hey!
Is there a way to add interior lighting to a model created in Blender, like the Bespin: Cloud City buildings? Is it just an msh.option command or was the lighting effect for those objects or to be precise the bes2_bldg_interior1.tga texture added in XSI? Because when I Import and Export a Bespin 2 building in Blender, like  bes2_bldg_mall, I don't get the same lighting effect in game, the interior is just dark (shadowvolume). Any contribution would be appreciated