Easy without pixel shaders, and just vertex shaders. Not really possible with no shaders at all, as you need to recompute the light direction vector, and attenuation for each vertex. You *could* calculate those values in software, put them in the vertex data (ie: direction in diffuse.rgb, and attenuation in diffuse.a would work)... but then you might as well just use software vertex processing and a vertex shader. (and, of course, hardware processing when shaders are available).