function center_image(obj) {	
	var img_box_img = new Object();
	img_box_img.e_width = 0;
	img_box_img.e_height = 0;
	var img_box = new Object();
	img_box.e_width = 0;
	img_box.e_height = 0;
	if(obj.clientWidth) img_box_img.e_width = obj.clientWidth;
	if(obj.clientHeight) img_box_img.e_height = obj.clientHeight;
	if(obj.parentNode.parentNode.clientWidth) img_box.e_width = obj.parentNode.parentNode.clientWidth;
	if(obj.parentNode.parentNode.clientHeight) img_box.e_height = obj.parentNode.parentNode.clientHeight;
	obj.style.position = 'absolute';
	obj.style.top = Math.round((img_box.e_height - img_box_img.e_height) / 2)+'px';
	obj.style.left = Math.round((img_box.e_width - img_box_img.e_width) / 2)+'px';
}