diff --git a/Lib/test/output/test_warnings b/Lib/test/output/test_warnings
new file mode 100644
index 0000000..9b45e42
--- /dev/null
+++ b/Lib/test/output/test_warnings
@@ -0,0 +1,10 @@
+test_warnings
+('ignore', False, 'FutureWarning', False, 0)
+('ignore', True, 'OverflowWarning', True, 0)
+('ignore', True, 'PendingDeprecationWarning', True, 0)
+Lib/test/test_warnings.py:31: UserWarning: hello world
+Lib/test/test_warnings.py:32: UserWarning: hello world
+Lib/test/test_warnings.py:33: DeprecationWarning: hello world
+Lib/test/test_warnings.py:35: UserWarning: hello world
+Caught UserWarning: hello world
+Caught AssertionError: invalid action: 'booh'
diff --git a/Lib/test/test_warnings.py b/Lib/test/test_warnings.py
new file mode 100644
index 0000000..9cd3c30
--- /dev/null
+++ b/Lib/test/test_warnings.py
@@ -0,0 +1,53 @@
+import warnings
+
+# The warnings module isn't easily tested, because it relies on module
+# globals to store configuration information.  We need to extract the
+# current settings to avoid bashing them while running tests.
+
+_filters = []
+_showwarning = None
+
+def showwarning(message, category, filename, lineno, file=None):
+    i = filename.find("Lib/")
+    filename = filename[i:]
+    print "%s:%s: %s: %s" % (filename, lineno, category.__name__, message)
+
+def monkey():
+    global _filters, _showwarning
+    _filters = warnings.filters[:]
+    _showwarning = warnings.showwarning
+    warnings.showwarning = showwarning
+
+def unmonkey():
+    warnings.filters = _filters[:]
+    warnings.showwarning = _showwarning
+
+def test():
+    for item in warnings.filters:
+        print (item[0], item[1] is None, item[2].__name__, item[3] is None,
+               item[4])
+    hello = "hello world"
+    for i in range(4):
+        warnings.warn(hello)
+    warnings.warn(hello, UserWarning)
+    warnings.warn(hello, DeprecationWarning)
+    for i in range(3):
+        warnings.warn(hello)
+    warnings.filterwarnings("error", "", Warning, "", 0)
+    try:
+        warnings.warn(hello)
+    except Exception, msg:
+        print "Caught", msg.__class__.__name__ + ":", msg
+    else:
+        print "No exception"
+    warnings.resetwarnings()
+    try:
+        warnings.filterwarnings("booh", "", Warning, "", 0)
+    except Exception, msg:
+        print "Caught", msg.__class__.__name__ + ":", msg
+    else:
+        print "No exception"
+
+monkey()
+test()
+unmonkey()
diff --git a/Lib/warnings.py b/Lib/warnings.py
index 1c55fb2..c2bc06e 100644
--- a/Lib/warnings.py
+++ b/Lib/warnings.py
@@ -9,8 +9,16 @@
 __all__ = ["warn", "showwarning", "formatwarning", "filterwarnings",
            "resetwarnings"]
 
-defaultaction = "default"
+# filters contains a sequence of filter 5-tuples
+# The components of the 5-tuple are:
+# - an action: error, ignore, always, default, module, or once
+# - a compiled regex that must match the warning message
+# - a class representing the warning category
+# - a compiled regex that must match the module that is being warned
+# - a line number for the line being warning, or 0 to mean any line
+# If either if the compiled regexs are None, match anything.
 filters = []
+defaultaction = "default"
 onceregistry = {}
 
 def warn(message, category=None, stacklevel=1):
@@ -69,9 +77,9 @@
     # Search the filters
     for item in filters:
         action, msg, cat, mod, ln = item
-        if (msg.match(text) and
+        if ((msg is None or msg.match(text)) and
             issubclass(category, cat) and
-            mod.match(module) and
+            (msg is None or mod.match(module)) and
             (ln == 0 or lineno == ln)):
             break
     else:
@@ -145,6 +153,21 @@
     else:
         filters.insert(0, item)
 
+def simplefilter(action, category=Warning, lineno=0, append=0):
+    """Insert a simple entry into the list of warnings filters (at the front).
+
+    A simple filter matches all modules and messages.
+    """
+    assert action in ("error", "ignore", "always", "default", "module",
+                      "once"), "invalid action: %s" % `action`
+    assert isinstance(lineno, int) and lineno >= 0, \
+           "lineno must be an int >= 0"
+    item = (action, None, category, None, lineno)
+    if append:
+        filters.append(item)
+    else:
+        filters.insert(0, item)
+
 def resetwarnings():
     """Clear the list of warning filters, so that no filters are active."""
     filters[:] = []
@@ -225,44 +248,6 @@
         raise _OptionError("invalid warning category: %s" % `category`)
     return cat
 
-# Self-test
-def _test():
-    import getopt
-    testoptions = []
-    try:
-        opts, args = getopt.getopt(sys.argv[1:], "W:")
-    except getopt.error, msg:
-        print >>sys.stderr, msg
-        return
-    for o, a in opts:
-        testoptions.append(a)
-    try:
-        _processoptions(testoptions)
-    except _OptionError, msg:
-        print >>sys.stderr, msg
-        return
-    for item in filters: print item
-    hello = "hello world"
-    warn(hello); warn(hello); warn(hello); warn(hello)
-    warn(hello, UserWarning)
-    warn(hello, DeprecationWarning)
-    for i in range(3):
-        warn(hello)
-    filterwarnings("error", "", Warning, "", 0)
-    try:
-        warn(hello)
-    except Exception, msg:
-        print "Caught", msg.__class__.__name__ + ":", msg
-    else:
-        print "No exception"
-    resetwarnings()
-    try:
-        filterwarnings("booh", "", Warning, "", 0)
-    except Exception, msg:
-        print "Caught", msg.__class__.__name__ + ":", msg
-    else:
-        print "No exception"
-
 # Module initialization
 if __name__ == "__main__":
     import __main__
@@ -270,5 +255,5 @@
     _test()
 else:
     _processoptions(sys.warnoptions)
-    filterwarnings("ignore", category=OverflowWarning, append=1)
-    filterwarnings("ignore", category=PendingDeprecationWarning, append=1)
+    simplefilter("ignore", category=OverflowWarning, append=1)
+    simplefilter("ignore", category=PendingDeprecationWarning, append=1)