function wopen(url, name, w, h)
{
// Fudge factors for window decoration space.
 // In my tests these work well on all platforms & browsers.
w += 32;
h += 96;
 var win = window.open(url,
  name, 
  'width=' + w + ', height=' + h + ', ' +
  'location=no, menubar=no, ' +
  'status=no, toolbar=no, scrollbars=yes, resizable=yes');
 win.resizeTo(w, h);
 win.focus();
}

function changeImages() {
	if (document.images && (preloadFlag == true)) {
		for (var i=0; i<changeImages.arguments.length; i+=2) {
			document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
		}
	}
}

function emailvalidation(field, alertbox) {
var goodEmail = field.value.match(/\b(^(\S+@).+((\.com)|(\.net)|(\.edu)|(\.mil)|(\.gov)|(\.org)|(\.info)|(\.sex)|(\.biz)|(\.aero)|(\.coop)|(\.museum)|(\.name)|(\.pro)|(\..{2,2}))$)\b/gi);
apos=field.value.indexOf("@");
dotpos=field.value.lastIndexOf(".");
lastpos=field.value.length-1;
var badEmail = (apos<1 || dotpos-apos<2 || lastpos-dotpos<2)
if (goodEmail && !badEmail) {
return true;
}
else {
alert(alertbox);
field.focus();
field.select();
return false;
   }
}
function emptyvalidation(entered, alertbox)
{
with (entered)
{
if (value==null || value=="")
{if (alertbox!="") {alert(alertbox);} return false;}
else {return true;}
}
}
function formvalidation(thisform)
{
with (thisform)
{

if (emptyvalidation(name,"Please enter your name")==false) {name.focus(); return false;};

if (emptyvalidation(lastname,"Please enter your last name")==false) {lastname.focus(); return false;};

if (emailvalidation(email,"Please enter your valid email address")==false) {email.focus(); return false;};

}

}