I am not completely sure I understand the question... can you elaborate and get a little more specific on the behavior?
Is it possible to do a dynamic impositions where the head & foot adjust with the page height,
example- if my page height is 11 inches and I want there to be 5 millimeters at the head and 5 millimeters at the foot,
then when I have a 10.75 page it ajust to the 10.75 with the 5mm head & foot., If this is posible how... Thanks.