This is pretty niche so I'm not expecting too much but...
I will probably be creating a PHP/MySQL based booking system, both clients and workers will be able to communicate with this system via their phones. Client communication will be handled via SMS messages, and I will be using a service called twilio ( http://www.twilio.com ). It allows me to submit all message data to a URL of my choice and from that I can process the contents via a PHP script.
To save on costs, I would like to run a similar system for internal communications using XMPP instead of SMS. Each staff member would be "friends" with a bot account. This account will send messages to staff as well as process incoming messages. All I want the bot to do is forward each incoming message to a PHP script at a URL of my choice (much like the twilio stuff above) so I can process the contents. I'd rather have a script be responsive to incoming text messages than have a PHP script run every minute or so to check for incoming messages.
So in summary, does anyone know of an XMPP client that can forward all contents to a URL via $_GET or $_POST?
Ta!
-Chris