function validate_signin() {
	var error_msg = ""
	
	if (!is_valid_email(document.getElementById("email").value)) {
		error_msg += "\n- You must use your email address to log in"
	}
	
	if (error_msg != "") {
		error_msg = "Please review the following and then press \"Submit\" again:\n" + error_msg
		alert(error_msg)
		return false
	} else {
		return true
	}
}