brought zircon branch into trunk

OpenSim.Framework/BlockingQueue.cs

@@ -0,0 +1,33 @@
+using System;
+using System.Threading;
+using System.Collections.Generic;
+using System.Text;
+
+namespace OpenSim.Framework.Utilities
+{
+    public class BlockingQueue<T>
+    {
+        private Queue<T> _queue = new Queue<T>();
+        private object _queueSync = new object();
+
+        public void Enqueue(T value)
+        {
+            lock (_queueSync)
+            {
+                _queue.Enqueue(value);
+                Monitor.Pulse(_queueSync);
+            }
+        }
+
+        public T Dequeue()
+        {
+            lock (_queueSync)
+            {
+                if (_queue.Count < 1)
+                    Monitor.Wait(_queueSync);
+
+                return _queue.Dequeue();
+            }
+        }
+    }
+}