var LastPosY = 0;

function move_DIV() {
	var y = (ns_pos)?window.pageYOffset:document.body.scrollTop;
	if (y!=LastPosY) {
		if (window.opera) {
			document.getElementById('preview_div_f').style.pixelTop=y;
		}
		else if (document.layers) {
			document.layers['preview_div_f'].top=y;
		}
		else if (document.getElementById) {
			document.getElementById('preview_div_f').style.top=y+'px';
		}
		else if (document.all) {
			document.all['preview_div_f'].style.pixelTop=y;
		}
		LastPosY=y;
	}
	if (TimeScroll)	window.setTimeout('move_DIV()','500');
}

var TimeScroll = true;

function InitFixed() {
	ns_pos = (typeof window.pageYOffset!='undefined');
	ie_pos = (document.body && typeof document.body.scrollTop!='undefined');
	window.onscroll=function(){window.onscroll=move_DIV;TimeScroll=false;};
	if (ns_pos||ie_pos) move_DIV();
	

}