How to calculate distance between latitude and longitude with a radius in Zend Lucene ?

Question

Hi,

I don't know if it's possible, but I would like to make a search on latitude, longitude, and a radius. I mean i'd like to get the distance between my reference latitude and longitude, compare it with all my stored latitude and longitude and if it's lesser than the radius, take it. Is it possible to do this whith Lucene (only if it's faster) ?

Thanks :)