Why don't you allow Chat applications?
HTTP was never designed for high refresh applications where a page is polled for updates every few seconds. For a chat application to update every 2 seconds, that involves (at least) a request every 2 seconds for every user chatting. For 4 users, that is 120 requests per minute, for just one site. Under normal usage, freeASPhost server process between 100 and 200 requests per minute; hence a couple of chat applications would put our usage far above that range. Therefore no-one is allowed chat applications.
Instead, try using an IRC server, or even messaging applications such as MSN Messenger, AIM, or ICQ.