function validation_stayup2date(){
	a = document.stayup2date;
 	if (a.email.value=="") {
		alert("Please enter your email address.");
		a.email.focus();
		a.email.select();
		return false;
	} else {
		var emailfilter=/^\w+[\+\.\w-]*@([\w-]+\.)*\w+[\w-]*\.([a-z]{2,4}|\d+)$/i
		var returnval=emailfilter.test(document.stayup2date.email.value)
		if (returnval==false) {
			alert("Please enter a valid email address.")
			document.stayup2date.email.select()
			return false;
		}
	}
	
	if (a.name.value=="") {
		alert("Please enter your name.");
		a.name.focus();
		a.name.select();
		return false;
	}
	
	if (a.role.value=="") {
		alert("Please enter your role.");
		a.role.focus();
		a.role.select();
		return false;
	}
	
	if (a.location.value=="") {
		alert("Please enter your location.");
		a.location.focus();
		a.location.select();
		return false;
	}
	
	if (a.working.value=="") {
		alert("Please enter for whom you are working.");
		a.working.focus();
		a.working.select();
		return false;
	}
	
	if (!(a.interest[0].checked || a.interest[1].checked || a.interest[2].checked || a.interest[3].checked)) {
		alert("Please select your main interest in Business Intelligence.");
 		return false;
	}
	return;
}