var imgwin = null;

window.addEvent('domready', function(){
	var links = $$('a.popup');
	links.each(function(item, index){
    	item.addEvent('click', function() {
    		var w = 500;
    		var h = 600;
			var padding = 0;
			var screenw = screen.availWidth;
			var screenh = screen.availHeight;
			var winw = (w + padding);
			var winh = (h + padding);
			var posx = (screenw / 2) - (winw / 2);
			var posy = (screenh / 2) - (winh / 2);

			var url=this.getAttribute('href');
			url = url + '?popup=1';
				
			if (imgwin) {
				imgwin.close();
			}
			
			imgwin = window.open(url,"imgwin","top="+posy+",left="+posx+",width="+winw+",height="+winh+",menubar=yes,locationbar=yes,statusbar=yes,resizable=yes,toolbar=no,dependent=yes,scrollbars=yes,X=0,Y=0");
			imgwin.focus(); 
			return !imgwin;			
    		
    	});
	});
});