function verify_guestbook()
{
	for(var i = 0; i < document.guestbook.elements.length; i++)
	{
		if((document.guestbook.elements[i].type=='text')&&(document.guestbook.elements[i].value==''))
		{
			document.guestbook.elements[i].className = document.guestbook.elements[i].className + ' required';
			document.guestbook.elements[i].focus();
			return false;
		}
		else if((document.guestbook.elements[i].type=='textarea')&&(document.guestbook.elements[i].value==''))
		{
			document.guestbook.elements[i].className = document.guestbook.elements[i].className + ' required';
			document.guestbook.elements[i].focus();
			return false;
		}
		else
		{
			document.guestbook.elements[i].className = document.guestbook.elements[i].className.replace(/required/g,'');
		}
	}
}