function window_load(e) {
// this function is fired when the page loaded
	setEventHandler(document.getElementById('frmTellAFriend'), 'submit', form_submit);
}

function form_submit(e) {
	var event = e ? e : window.event;
	var frm = event.target ? event.target : event.srcElement;
	var isValid = true;
	
	// validate the form fields
	if (frm.txtFirstName.value == '') {
		alert('You must enter your first name.');
		frm.txtFirstName.focus();
		isValid = false;
	}	
	else if (frm.txtLastName.value == '') {
		alert('You must enter your last name.');
		frm.txtLastName.focus();
		isValid = false;
	}	
	else if (frm.txtSendToEmail.value == '') {
		alert('You must enter at least one friend\'s email address.');
		frm.txtSendToEmail.focus();
		isValid = false;
	}
	else if (!validEmail(frm.txtSendToEmail.value)) {
		alert('The email address you entered for your friend appears to be invalid. Please make sure the email address is correct.');
		frm.txtSendToEmail.focus();
		isValid = false;
	}
	else if (frm.txtSendToEmail2.value != '' && !validEmail(frm.txtSendToEmail2.value)) {
		alert('The email address you entered for your friend appears to be invalid. Please make sure the email address is correct.');
		frm.txtSendToEmail2.focus();
		isValid = false;
	}
	else if (frm.txtSendToEmail3.value != '' && !validEmail(frm.txtSendToEmail3.value)) {
		alert('The email address you entered for your friend appears to be invalid. Please make sure the email address is correct.');
		frm.txtSendToEmail3.focus();
		isValid = false;
	}
	else if (frm.txtSendToEmail4.value != '' && !validEmail(frm.txtSendToEmail4.value)) {
		alert('The email address you entered for your friend appears to be invalid. Please make sure the email address is correct.');
		frm.txtSendToEmail4.focus();
		isValid = false;
	}
	else if (frm.txtSendToEmail5.value != '' && !validEmail(frm.txtSendToEmail5.value)) {
		alert('The email address you entered for your friend appears to be invalid. Please make sure the email address is correct.');
		frm.txtSendToEmail5.focus();
		isValid = false;
	}
	
	// stop the form submission if necessary
	if (!isValid) {
		if (event.preventDefault) {				
			event.preventDefault();			
		}
		
		return isValid;
	}
}

// set page events
setEventHandler(window, 'load', window_load);