This request would be more along the lines of an aknowledgement that the client is still connected and has received the response.
Does this seem possible??
Netscape Server Push - introduced in ver 1.1 - seems to be what you mean: http://www.netscape.com/home/demo/1.1b1/pushpull.html
Still work with version 4.7, although the animation at the above URL doesn't. Try http://www.theriver.com/trwrc/serverpush.html for a demo. No idea about Mozilla.
I haven't read the whole thread, so forgive me if this is out of turn... A cross-browser solution might be to start a new browser window pointing to a "connectMonitor" URL on your server, that requests a client-side refresh every 10 seconds (or 10 minutes or whatever you need). This is done with a simple META tag in the <HEAD> section of the HTML doc. <META HTTP-EQUIV="Refresh" content="32;URL=http://myserver.net/connectMonitor"> Assuming 'connectMonitor' is the name of the URL serving up this page. This example makes the client wait 32 seconds and then repoll; change the number to anything you want (zero makes an immediate refresh). Easy to do, and it's standard HTML/HTTP. When you want to publish a new message to all connected users, have your 'connectMonitor' method hook a bit of Javascript on the document's onLoad() event, which will open a new browser window at the URL representing your message. (Or I guess you could just include the message in the 'connectMonitor' page if it's something that is transient.) -- Graham