function swap_images(a_tag, number)
{
	for(i=1;i<=8;i++){
		if(document.getElementById("img_"+i)){
			img_small = document.getElementById("img_"+i);
			str = img_small.src;
			if (i == number)
			img_small.src = str.substr(0, str.lastIndexOf("/"))+"/portfolio_minus.gif";
			else
			img_small.src = str.substr(0, str.lastIndexOf("/"))+"/portfolio_plus.gif";
		}
	}

	var img_big = document.getElementById('img_0');img_big.innerHTML = "&nbsp;";
	var img = new Image();img.src = a_tag.href;
	img_big.innerHTML = "<img src=\""+img.src+"\" />";
	a_tag.blur();
	return false;
}

function show_banner(banner_file, width, height)
{
	Bwin = window.open(banner_file, 'Banner','width='+width+',height='+height+',directories=no,toolbar=no,addressbar=no,resizable=no,menubar=no,scrollbars=no');
	Bwin.focus();
	return false;
}