Ok, just to extend this thought.
http://community.jboss.org/servlet/JiveServlet/downloadImage/2-628448-17054/450-104/Capture2.PNG
I had a look at the evaluation example. Both mary and john receive human tasks in the tasklist at the same time.
Event though these tasks are triggered sequentially after each other. I guess that is possible, because the human task handlers are asynchonous.
But lets imagine the node on top would be an intermediate message receive event node and the one on the bottom a timer event node. If the receive node is entered first, the process would be waiting until a message comes and the timer would not be executed (until the message comes in). Vice versa, if the timer is entered first, the timer would be finished and then the receive node would be activated (and waiting).
