var snapFooter = function() {
	var viewportHeight = YAHOO.util.Dom.getViewportHeight();
	
	var hdRegion = YAHOO.util.Dom.getRegion('hd');
	var hdHeight = hdRegion.bottom - hdRegion.top;
	
	var bdRegion = YAHOO.util.Dom.getRegion('bd');
	var bdHeight = bdRegion.bottom - bdRegion.top;
	
	var ftRegion = YAHOO.util.Dom.getRegion('ft');
	var ftHeight = ftRegion.bottom - ftRegion.top;
	
	if ((viewportHeight - hdHeight - bdHeight - ftHeight) >= 0) {
		YAHOO.util.Dom.setStyle('bd', 'height', (viewportHeight - hdHeight - ftHeight)+'px');
	}
}();