lighting problem

i created an object and edited its faces and such to my liking, gave textures and light to them all. but it seems like the faces that i made, the lighting is reversed on them. meaning blackness is towards the light but on the original parts of the mesh(in this case a tube) the light is correct. i tryed vertex lighting but still the same problem. i move the lighting so that it was right infront of the faces and they still showed up black but the opposite side was lite(also with spot lights). i tried giving it a material and changing specularity as well. the shape is basiclly a pipe but with rounded ends and it is these ends that it does this. i cant get you an image so here is a ruff drawing.

@ (lamp)

              ____________     <- light

dark-> /
light-> ------------- <- dark

dark-> /------------- <- light
light-> ____________

im sorry if this is a newb question its just late and this is seriously annoying me.

are your faces doublesided?

you probably have normals pointing the wrong way [recalc with control+n, turn off double sided in edit buttons and the back side of your faces will turn black]

but the thing is, if your normals point the wrong way, unless the face is double sided it will probably just be invisible from the back side

for the most part you should avoid using double sided faces anyway [performance increase on some hardware]

ack i didnt know about that control+n thing, thanks again