OK, I was just being stupid...I'm answering the question in case someone else looks at this issue.
I had set the origin of the bezier to the endpoint of one of the handles...I thought it was on the actual endpoint of the curve.
As a result, even though the origins were lined up and scaled & rotated the same, the modifier was placing the objects with an offset. It LOOKED like it was going right through the center of the mass of the created objects, but this was just a coincidence.
So...if you have this problem, check your origins again! Make sure the endpoint of the spline is placed exactly where you want it and its origin is on the endpoint, not the handle.
thanks for the replies.