Thread 1				Thread2
X1=2					X2=2
=================================================================
Step A -> "S:X:1:1"
Step B -> 1 message (ours) to process.
Step C -> return 2
------------------------------------------- Timeslice
						Step A ->  "S:X:2:4"
						Step B -> 1 msg to process
							   -> "S:X:2:4"
						Step C -> return 2
------------------------------------------- Timeslice
Step D -> 2+1 = 3
Step E -> "A:X:1:7:3" 
Step F -> X1=3
	   -> Enqueue "A:X:1:9:3" -> T2
------------------------------------------- Timeslice
						Step D -> 2+1=3
						Step E -> "A:X:2:11:3"
						Step F -> 2 msgs to process
						       -> "A:X:1:9:3"  -> X2=3
						       -> "A:X:2:11:3" -> X2=3 !!!Bang!!!
=================================================================