Port 5000

We are seeing many customers here probing port 5000 across the network. It appears to be some new worm or something but I've had no luck yet in figuring out what it is except to say norton AV detects nothing yet. Anyone have a clue? http://isc.incidents.org/port_details.php?isc=b4827221b7f45feeb0c12bc5040cab c9&port=5000&repax=1&tarax=2&srcax=2&percent=N&days=10&Redraw=Submit+Query the jump in traffic is obvious. Geo.