diff --git a/Lib/test/test_threadsignals.py b/Lib/test/test_threadsignals.py
new file mode 100644
index 0000000..ad983c0
--- /dev/null
+++ b/Lib/test/test_threadsignals.py
@@ -0,0 +1,77 @@
+"""PyUnit testing that threads honor our signal semantics"""
+
+import unittest
+import thread
+import signal
+import os
+from test import test_support
+
+signal_blackboard = { signal.SIGUSR1 : {'tripped': 0, 'tripped_by': 0 }, 
+                      signal.SIGUSR2 : {'tripped': 0, 'tripped_by': 0 },
+                      signal.SIGALRM : {'tripped': 0, 'tripped_by': 0 } }
+
+process_pid = os.getpid()
+signalled_all=thread.allocate_lock()
+
+
+def registerSignals((for_usr1, for_usr2, for_alrm)):
+    usr1 = signal.signal(signal.SIGUSR1, for_usr1)
+    usr2 = signal.signal(signal.SIGUSR2, for_usr2)
+    alrm = signal.signal(signal.SIGALRM, for_alrm)
+    return usr1, usr2, alrm
+
+
+# The signal handler. Just note that the signal occured and
+# from who.
+def handle_signals(sig,frame):
+    signal_blackboard[sig]['tripped'] += 1 
+    signal_blackboard[sig]['tripped_by'] = thread.get_ident()
+
+# a function that will be spawned as a separate thread.
+def send_signals():
+    os.kill(process_pid, signal.SIGUSR1)
+    os.kill(process_pid, signal.SIGUSR2)
+    signalled_all.release()
+
+class ThreadSignals(unittest.TestCase):
+    """Test signal handling semantics of threads.
+       We spawn a thread, have the thread send two signals, and
+       wait for it to finish. Check that we got both signals
+       and that they were run by the main thread.
+    """
+    def test_signals(self):
+        signalled_all.acquire()
+        self.spawnSignallingThread()
+        signalled_all.acquire()
+        # the signals that we asked the kernel to send
+        # will come back, but we don't know when.
+        # (it might even be after the thread exits
+        # and might be out of order.)  If we haven't seen
+        # the signals yet, send yet another signal and
+        # wait for it return.
+        if signal_blackboard[signal.SIGUSR2]['tripped'] == 0 \
+           or signal_blackboard[signal.SIGUSR2]['tripped'] == 0:
+             signal.alarm(1)
+             signal.pause()
+             signal.alarm(0)
+
+        self.assertEqual( signal_blackboard[signal.SIGUSR1]['tripped'], 1)
+        self.assertEqual( signal_blackboard[signal.SIGUSR1]['tripped_by'], 
+                           thread.get_ident())
+        self.assertEqual( signal_blackboard[signal.SIGUSR2]['tripped'], 1)
+        self.assertEqual( signal_blackboard[signal.SIGUSR2]['tripped_by'], 
+                           thread.get_ident())
+
+    def spawnSignallingThread(self):
+        thread.start_new_thread(send_signals, ())
+        
+
+def test_main():
+    oldsigs = registerSignals((handle_signals, handle_signals, handle_signals))
+    try:
+        test_support.run_unittest(ThreadSignals)
+    finally:
+        registerSignals(oldsigs)
+
+if __name__ == '__main__':
+    test_main()