dupp
One of your queues is having issues. I don't know which one as it's not providing the Queue ID so you might have to go to the database and disable each queue until the error goes away. Once you find the queue causing issues you can make note of the criteria, completely delete the queue, and recreate the queue. After you've done this you should be fine.
The way you can "disable" a queue is to make note of the current staff_id, set the staff_id to 999 (basically a staff ID that doesn't exist), and then change it back to it's original value after you've addressed the issue.
Cheers.
