I want mapspots getting larger when zooming in

Hi,
is there a way to do this? I made some own different mapspots and need them to get larger when zooming in. i.e. if I want to show a house on the map I want the mapspot to be quite large when I zoomed into the closest level - without this my spot too small, nearly undetectable...
I defined my spots over the <spot /> tag....

sorry, actually not. But I think it's a generell question without needing any examples:
the standard mappoints behave like I described: they are keeping their dimensions when zooming into the map. What I want is the mapspots to behave like the map itself: getting larger when zooming in.