function $(id)
{
	return document.getElementById(id);
}
/**/
function addLoadEvent(func)
{
	var oldonload = window.onload;
	if (typeof window.onload != 'function') {
		window.onload = func;
	} else {
		window.onload = function() {
			if (oldonload) {oldonload();} func();
		}
	}
}
/**/
function openWin(url, ancho, alto) {
	var day = new Date();
	var id  = day.getTime();
	var w   = screen.width;
  var h   = screen.height;
	var leftPos = (w-ancho)/2;
	var topPos = (h-alto)/2;

	eval("page" + id +
		 " = window.open(url, '" + id + "', '" +
		 "toolbar=0,"   +
		 "scrollbars=1,"+
		 "statusbar=0," +
		 "menubar=0,"   +
		 "resizable=0," +
		 "width="+ ancho + "," +
		 "height="+ alto + "," +
		 "top="+ topPos + ","  +
		 "left="+ leftPos +"');");
}