// JavaScript Document
function submitForm() {
 var g = true;
 if (document.contact.email.value == "") {
    window.alert("You must enter your email address to submit form!");
	document.contact.email.focus(); 
	var g = false;
	return false;
 }
		re = /^[a-zA-Z0-9]+([-_\.]?[a-zA-Z0-9])+@[a-zA-Z0-9]+([-_\.]?[a-zA-Z0-9])+\.[a-zA-Z\.]{2,4}/      //  /^\w+$/; 
		if(!re.test(document.contact.email.value)) { 
			alert("Error: email must contain only letters, numbers, dash, dot,\n underscores(first part), and the 'at' sign!");    // @
			document.contact.email.focus(); 
			var g = false;
			return false; 
		}   	
 
	if (g != false) {
		return true;
	}
}  // end function   p261 gosselin book