// Check if email is valid
function valid_email($email,$check_mx=false) {
$email_pattern = ‘/^\w+((-\w+)|(_\w+)|(\.\w+))*\@[a-z0-9]+((\.|-)[a-z0-9]+)*\.[a-zA-Z]{2,6}$/’;
$return = false;
if (preg_match($email_pattern,strtolower($email)))
$return = true;

if ($return && $check_mx) {
list($user,$host) = split(‘@’,$email);
$host .= ‘.’;
if ( getmxrr( $host, $mxhosts ) == false && gethostbyname( $host ) == $host )
$return = false;
else
$return = true;
}
return $return;
}