function popup(url,name,width,height) {
        if (! width) { width=525; }
        if (! height) { height=600; }
        popwindow=window.open(url,name,'menubar,resizable,scrollbars,dependent,width='+width+',height='+height+',left=164,top=4');
}

function roll(image1, reference1) {
  if (document.images)
    document.images[image1].src = reference1;
}

function IsEmpty(aTextField) {
   if ((aTextField.value.length==0) || (aTextField.value==null)) { return true; }
   else { return false; }
}

// _w : which ID (1) or (2)
// _h : (h)ide or (s)how
function toggleT(_w,_h) {
	if (document.all) { // is IE
		if (_h=='s') eval("document.all."+_w+".style.visibility='visible';");
		if (_h=='h') eval("document.all."+_w+".style.visibility='hidden';");
	} 
	else { // is NS? 
		if (_h=='s') eval("document.layers['"+_w+"'].visibility='show';");
		if (_h=='h') eval("document.layers['"+_w+"'].visibility='hide';");
	}
}