How to attach a circular body to a sprite off center!

I am trying to attach a circular body to a sprite but not at the center of it, I want to attach it to the bottom. Does anyone know how to do this?
[import]uid: 8192 topic_id: 3726 reply_id: 303726[/import]

circle=display.newCircle( sprite.x, (sprite.y+(sprite.stageHeigh*0.5)), circlesize)

Put you sprites name in place of sprite and the size of the circle in place of circlesize [import]uid: 7911 topic_id: 3726 reply_id: 11490[/import]