--- Operating System, Graphics card ---
Ubuntu Quantal 64bits
GeForce GTX 460

--- Blender version with error, and version that worked ---
Reproduced on 2.65.9 64bits (r54314) and 2.66 testbuild1
Works on 2.65a on simple scene (as attached), but doesn't on complex one (too big to upload).

--- Short description of error ---
Indirect Lighting on a scene stops working after starting & stopping game engine, and won't work ever on blend file and existing materials.

--- Steps for others to reproduce the error (preferably based on attached .blend file) ---
Open ilbug.blend
Render with F12 -> red indirect lighting ok
Hit 'P', then Escape
Render again with F12 -> indirect lighting gone
Found no way to have it back on this blend file and material, creating a new material gets it back on this new material as long as 'P' is not run again.