Thanks for the response.
I'm having a little issue with the segment shape for some odd reason.
I've added a single segment shape. it's the same code as in the cocos2d-chipmunk template (for creating the walls).
I changed the coordinates to match the right-side of an inner wall (red line in the pic).
shape = cpSegmentShapeNew(staticBody, cpv(120,wins.height), cpv(120,wins.height-75), 0.0f);
shape->e = 1.0f; shape->u = 1.0f;
cpSpaceAddStaticShape(space, shape);

The problem is that somehow, that single line has a thickness to it for some reason...
if I collide into it from the other side, I would assume the ball to get on top the "metal bar" and hit the red line from the other side.
but what's happening is that the ball is colliding in mid-air, about 15points to the left of the red line (blue line in the pic).

maybe it's because I'm using the same staticBody the floor was using...? I'll try to open a different one.
Just to be clear: the segment shape takes an (x,y) of the first point & and (x,y) of the second point and "draws" a straight line between them, right? what is the 3rd parameter? (the 0.0f)
Thanks a bunch!