diff --git a/src/callbacks.py b/src/callbacks.py
index f436ce1ac..93815743c 100644
--- a/src/callbacks.py
+++ b/src/callbacks.py
@@ -327,7 +327,13 @@ class IrcObjectProxy:
             if self.finished:
                 break
             if hasattr(cb, 'invalidCommand'):
-                cb.invalidCommand(self, self.msg, self.args)
+                try:
+                    cb.invalidCommand(self, self.msg, self.args)
+                except Exception, e:
+                    cb.log.exception('Uncaught exception in invalidCommand:')
+                    log.warning('Uncaught exception in %s.invalidCommand, '
+                                'continuing to call other invalidCommands.' %
+                                cb.name())
                 
     def finalEval(self):
         assert not self.finalEvaled, 'finalEval called twice.'
@@ -433,6 +439,7 @@ class IrcObjectProxy:
                 if len(s) < allowedLength:
                     self.irc.queueMsg(reply(msg, s, self.prefixName,
                                             self.private,self.notice,self.to))
+                    self.finished = True
                     return
                 msgs = textwrap.wrap(s, allowedLength-30) # -30 is for "nick:"
                 msgs.reverse()
diff --git a/test/test_callbacks.py b/test/test_callbacks.py
index 3ed7a3da2..203e36252 100644
--- a/test/test_callbacks.py
+++ b/test/test_callbacks.py
@@ -323,6 +323,35 @@ class PrivmsgTestCase(ChannelPluginTestCase):
     def testNoEscapingAttributeErrorFromTokenizeWithFirstElementList(self):
         self.assertError('[plugin list] list')
 
+    class InvalidCommand(callbacks.Privmsg):
+        def invalidCommand(self, irc, msg, tokens):
+            irc.reply(msg, 'foo')
+
+    def testInvalidCommandOneReplyOnly(self):
+        try:
+            original = conf.replyWhenNotCommand
+            conf.replyWhenNotCommand = True
+            self.assertRegexp('asdfjkl', 'not a valid command')
+            self.irc.addCallback(self.InvalidCommand())
+            self.assertResponse('asdfjkl', 'foo')
+            self.assertNoResponse(' ', 2)
+        finally:
+            conf.replyWhenNotCommand = original
+
+    class BadInvalidCommand(callbacks.Privmsg):
+        def invalidCommand(self, irc, msg, tokens):
+            s = 'This shouldn\'t keep Misc.invalidCommand from being called'
+            raise Exception, s
+        
+    def testBadInvalidCommandDoesNotKillAll(self):
+        try:
+            original = conf.replyWhenNotCommand
+            conf.replyWhenNotCommand = True
+            self.irc.addCallback(self.BadInvalidCommand())
+            self.assertRegexp('asdfjkl', 'not a valid command')
+        finally:
+            conf.replyWhenNotCommand = original
+            
 
 class PrivmsgCommandAndRegexpTestCase(PluginTestCase):
     plugins = ('Utilities',) # Gotta put something.