var ie = (document.all)? true : false;
var nn6 = (!ie && document.getElementById)? true : false;
var nn4 = (document.layers)? true : false;
if (!(window.name=='gretta')) 
{ 
 window.name='gretta';
}
function popupWin(name, uri, wdt, hgt) {
var posCode = '';
if (nn4 || nn6 || ie) {
if ( (screen.height < 481) && (hgt > 400) ) { hgt = 400 }
posX = Math.round((screen.width - wdt) / 2);
posY = Math.round((screen.height - hgt) / 2);
posCode = (nn4 || nn6)? ",screenX="+posX+",screenY="+posY : ",left="+posX+",top="+posY;
}
popupedWin = window.open(uri, name, "status=no,menubar=no,toolbar=no,resizable=yes,scrollbars=no,location=no,width="+wdt+",height="+hgt+posCode);
popupedWin.focus();
	}