function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}

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];
		}
	}
}

var preloadFlag = false;
function preloadImages() {
	if (document.images) {
		intro_over = newImage("/images/sidenav/intro-over.gif");
		essays_over = newImage("/images/sidenav/essays-over.gif");
		readings_over = newImage("/images/sidenav/readings-over.gif");
		calendar_over = newImage("/images/sidenav/calendar-over.gif");
		testimonials_over = newImage("/images/sidenav/testimonials-over.gif");
		buy_over = newImage("/images/sidenav/buy-over.gif");
		contact_over = newImage("/images/sidenav/contact-over.gif");
		tribal_lynx_over = newImage("/images/sidenav/tribal_lynx-over.gif");
		john_over = newImage("/images/sidenav/john-over.gif");
		chris_over = newImage("/images/sidenav/chris-over.gif");
		preloadFlag = true;
	}
}

// basic validation for payment form
function checkPayForm(form) {
	var msg = "";
	
	if (/^\s*$/.test(form.FirstName.value)) {
		msg += "Please enter your first name.\n";
	}
	
	if (/^\s*$/.test(form.LastName.value)) {
		msg += "Please enter your last name.\n";
	}
	
	if (!/^([0-9a-zA-Z]([-.\w]*[0-9a-zA-Z])*@([0-9a-zA-Z][-\w]*[0-9a-zA-Z]\.)+[a-zA-Z]{2,9})$/.test(form.Email.value)) {
		msg += "Please enter a valid email address.\n";
	}
	
	if (/^\s*$/.test(form.Address1.value)) {
		msg += "Please enter your address.\n";
	}
	
	if (/^\s*$/.test(form.City.value)) {
		msg += "Please enter your city.\n";
	}
	
	if (/^\s*$/.test(form.State.value)) {
		msg += "Please select your state (if you reside outside the US, please select \"Outside USA\").\n";
	}
	
	if (/^\s*$/.test(form.Zip.value)) {
		msg += "Please enter your postal code.\n";
	}
	
	if (/^\s*$/.test(form.Phone.value)) {
		msg += "Please enter your phone number.\n";
	}
	
	if (msg) {
		//msg = "The form could not be submitted for the following reasons:\n\n"+msg;
		alert(msg);
		return false;
	}
}