var cur_top = 0; 
var cur_top2 = 600; 
var div_height2 = document.all["page_top"].offsetHeight +180;
var tot_height = document.body.scrollHeight;

function banner_move(){
	tot_height = document.body.scrollHeight;
	cur_top = document.body.scrollTop+0;
	cur_top2 = document.body.scrollTop+600;

	if(cur_top2 > (tot_height-div_height2)){
		cur_top2 = (tot_height-div_height2);
	}

 	document.all["page_top"].style.pixelTop += (cur_top2-document.all["page_top"].style.pixelTop)/10;

	setTimeout("banner_move()",10);
}
document.body.onload = banner_move;