diff --git a/eventlet/coros.py b/eventlet/coros.py
index 66e0820..a41d449 100644
--- a/eventlet/coros.py
+++ b/eventlet/coros.py
@@ -262,6 +262,7 @@ class Semaphore(object):
 
     def __init__(self, count=0):
         self.counter  = count
+        self._order = collections.deque()
         self._waiters = {}
 
     def __str__(self):
@@ -280,6 +281,7 @@ class Semaphore(object):
             return False
         while self.counter<=0:
             self._waiters[api.getcurrent()] = None
+            self._order.append(api.getcurrent())
             try:
                 api.get_hub().switch()
             finally:
@@ -293,14 +295,21 @@ class Semaphore(object):
     def release(self, blocking=True):
         # `blocking' parameter is for consistency with BoundedSemaphore and is ignored
         self.counter += 1
-        if self._waiters:
+        if self._waiters or self._order:
             api.get_hub().schedule_call_global(0, self._do_acquire)
         return True
 
     def _do_acquire(self):
-        if self._waiters and self.counter>0:
-            waiter, _unused = self._waiters.popitem()
-            waiter.switch()
+        if (self._waiters or self._order) and self.counter>0:
+            waiter = None
+            while not waiter and self._order:
+                waiter = self._order.popleft()
+                if waiter not in self._waiters:
+                    waiter = None
+
+            if waiter is not None:
+                self._waiters.pop(waiter)
+                waiter.switch()
 
     def __exit__(self, typ, val, tb):
         self.release()
diff --git a/greentest/test__coros_queue.py b/greentest/test__coros_queue.py
index 7a1d616..77939ac 100644
--- a/greentest/test__coros_queue.py
+++ b/greentest/test__coros_queue.py
@@ -73,7 +73,7 @@ class TestQueue(LimitedTestCase):
         self.assertEquals(e2.wait(),'hi')
         self.assertEquals(e1.wait(),'done')
 
-    def skip_test_multiple_waiters(self):
+    def test_multiple_waiters(self):
         q = coros.queue()
 
         def waiter(q, evt):
@@ -164,7 +164,7 @@ class TestQueue(LimitedTestCase):
         self.assertEquals(e2.wait(), 'timed out')
         self.assertEquals(q.wait(), 'sent')
 
-    def disable_test_waiting(self):
+    def test_waiting(self):
         def do_wait(q, evt):
             result = q.wait()
             evt.send(result)
@@ -175,6 +175,7 @@ class TestQueue(LimitedTestCase):
         api.sleep(0)
         self.assertEquals(1, waiting(q))
         q.send('hi')
+        api.sleep(0)  # *FIX this should not be necessary
         self.assertEquals(0, waiting(q))
         self.assertEquals('hi', e1.wait())
         self.assertEquals(0, waiting(q))