function validate_email()
{
	// valid, error message, email error, email both
	v = true, e_msg, e_e = false, e_b = false;
	
	st_n = getById("r_student_name");
	st_e = getById("re_student_email");
	pr_n = getById("r_prof_name");
	pr_e = getById("re_prof_email");
	
	var e_ = getById("mailformheader");
	
	if (st_n.value == "") { v = false; e_msg = "Please fill out the form completely."; }
	if (st_e.value == "") { v = false; e_msg = "Please fill out the form completely."; }
	if (pr_n.value == "") { v = false; e_msg = "Please fill out the form completely."; }
	if (pr_e.value == "") { v = false; e_msg = "Please fill out the form completely."; }

	var rxp = new RegExp("^[a-zA-Z][\\w\\.-]*[a-zA-Z0-9]@[a-zA-Z0-9][\\w\\.-]*[a-zA-Z0-9]\\.[a-zA-Z][a-zA-Z\\.]*[a-zA-Z]$");
	var st_match = rxp.exec(st_e.value), pr_match = rxp.exec(pr_e.value);

	if (st_match == null) { v = false; }
	if (pr_match == null)
	{ 
		v = false; 
		if (st_match == null)
		{ 
			e_b = true;
		}
	}

	if(!v)
	{
		if(e_e)
		{
			if (e_b)
			{
				e_msg = "\""+st_e.value+"\" and \""+pr_e.value+"\" are not valid email addresses.";
			} else {
				if (st_match == null) { e_msg = "\""+st_e.value+"\" is not a valid email address."; }
				if (pr_match == null) { e_msg = "\""+pr_e.value+"\" is not a valid email address."; }
			}
			e_.innerHTML = e_msg;
		} else {
			e_.innerHTML = e_msg;
		}
		return false;
	} else {
		return true;
	}
}