[Pr0Head]

<form name="subscribe" method="get" action="subscribe.php">
<input type="text" name="email">
<input type=hidden name="action">
<input type=submit value="Подписаться" onClick="document.subscribe.action.value='subscribe'"><input type=submit value="Отписаться"onClick="document.subscribe.action.value='unsubscribe'">
</form>