function popUp( URL, name, popW, popH ) {

	var w = 480, h = 340;
	
	if (document.all || document.layers || document.getElementById) {
	   w = screen.availWidth;
	   h = screen.availHeight;
	}
	
	var topPos = (h-popH)/2;
	var leftPos = (w-popW)/2;
	
	window.open(URL,name,'resizable=no, toolbar=no, location=no, status=no, scrollbars=yes, menubar=no, titlebar=no, width=' + 
				popW + ',height=' + popH + ',left=' + leftPos + ',top=' + topPos + ',screenX=' + leftPos + ',screenY=' + topPos);
   
}