see the attached screenshot :

I am making a material with normal maps (EMT_NORMAL_MAP_SOLID). Unfortunately for some reason I can't figure out, the faces that face away from the directional light are pitch-black - even though the scene has an ambient light (scene_manager->setAmbientLight) and even though I too gave an ambient color to the material in question.
This is irrlicht SVN (trunk r3842) on OS X 10.6
Anyone has any clue what's going on there?