diff --git a/mopidy/exceptions.py b/mopidy/exceptions.py
new file mode 100644
index 00000000..8f352807
--- /dev/null
+++ b/mopidy/exceptions.py
@@ -0,0 +1,6 @@
+class MpdAckError(Exception):
+    pass
+
+class MpdNotImplemented(MpdAckError):
+    def __init__(self, *args):
+        super(MpdNotImplemented, self).__init__(u'Not implemented', *args)
diff --git a/mopidy/handler.py b/mopidy/handler.py
index 823f9a0c..a9808f7c 100644
--- a/mopidy/handler.py
+++ b/mopidy/handler.py
@@ -4,6 +4,7 @@ import sys
 
 from mopidy import settings
 from mopidy.backends.spotify import SpotifyBackend
+from mopidy.exceptions import MpdAckError, MpdNotImplemented
 
 logger = logging.getLogger('handler')
 
@@ -18,26 +19,40 @@ def register(pattern):
         return func
     return decorator
 
+def flatten(the_list):
+    result = []
+    for element in the_list:
+        if isinstance(element, list):
+            result.extend(flatten(element))
+        else:
+            result.append(element)
+    return result
+
 class MpdHandler(object):
     def __init__(self, session=None, backend=None):
         self.session = session
         self.backend = backend
+        self.command_list = False
 
-        self.buffer = False
-
-    def handle_request(self, request):
+    def handle_request(self, request, add_ok=True):
+        if self.command_list is not False and request != u'command_list_end':
+            self.command_list.append(request)
+            return None
         for pattern in _request_handlers:
             matches = re.match(pattern, request)
             if matches is not None:
                 groups = matches.groupdict()
-                response = _request_handlers[pattern](self, **groups)
-                if self.buffer:
-                    self.response_buffer.append(response)
+                result = _request_handlers[pattern](self, **groups)
+                if self.command_list is not False:
                     return None
-                else:
-                    return response
+                response = []
+                if result is not None:
+                    response.append(result)
+                if add_ok:
+                    response.append(u'OK')
+                return flatten(response)
         logger.warning(u'Unhandled request: %s', request)
-        return False
+        raise MpdAckError(u'Unhandled request: %s' % request)
 
     @register(r'^add "(?P<uri>[^"]*)"$')
     def _add(self, uri):
@@ -62,13 +77,26 @@ class MpdHandler(object):
 
     @register(r'^command_list_begin$')
     def _command_list_begin(self):
-        self.response_buffer = []
-        self.buffer = True
+        self.command_list = []
+        self.command_list_ok = False
+
+    @register(r'^command_list_ok_begin$')
+    def _command_list_ok_begin(self):
+        self.command_list = []
+        self.command_list_ok = True
 
     @register(r'^command_list_end$')
     def _command_list_end(self):
-        self.buffer = False
-        return self.response_buffer
+        (command_list, self.command_list) = (self.command_list, False)
+        (command_list_ok, self.command_list_ok) = (self.command_list_ok, False)
+        result = []
+        for command in command_list:
+            response = self.handle_request(command, add_ok=False)
+            if response is not None:
+                result.append(response)
+            if command_list_ok:
+                response.append(u'list_OK')
+        return result
 
     @register(r'^consume "(?P<state>[01])"$')
     def _consume(self, state):
@@ -121,10 +149,9 @@ class MpdHandler(object):
     def _kill(self):
         self.session.do_kill()
 
-    @register(r'^list (?P<type>(artist|album))( (?P<artist>.*))*$')
+    @register(r'^list (?P<type>artist)$')
+    @register(r'^list (?P<type>album)( (?P<artist>.*))*$')
     def _list(self, type, artist=None):
-        if type == u'artist' and artist is not None:
-            return False
         pass # TODO
 
     @register(r'^listall "(?P<uri>[^"]+)"')
diff --git a/mopidy/session.py b/mopidy/session.py
index 1cfb7cd0..4d39549d 100644
--- a/mopidy/session.py
+++ b/mopidy/session.py
@@ -2,6 +2,7 @@ import asynchat
 import logging
 
 from mopidy import get_mpd_version, settings
+from mopidy.exceptions import MpdAckError
 from mopidy.handler import MpdHandler
 
 logger = logging.getLogger(u'session')
@@ -36,10 +37,11 @@ class MpdSession(asynchat.async_chat):
         self.handle_request(input)
 
     def handle_request(self, input):
-        response = self.handler.handle_request(input)
-        self.handle_response(response)
-        if not self.handler.buffer:
-            self.send_response(u'OK')
+        try:
+            response = self.handler.handle_request(input)
+            self.handle_response(response)
+        except MpdAckError, e:
+            self.send_response(u'ACK %s' % e)
 
     def handle_response(self, response):
         if isinstance(response, list):
diff --git a/tests/handlertest.py b/tests/handlertest.py
index 5ee0f2b3..2c249592 100644
--- a/tests/handlertest.py
+++ b/tests/handlertest.py
@@ -2,6 +2,7 @@ import unittest
 
 from mopidy import handler
 from mopidy.backends.dummy import DummyBackend
+from mopidy.exceptions import MpdAckError
 
 class RequestHandlerTest(unittest.TestCase):
     def setUp(self):
@@ -16,32 +17,58 @@ class RequestHandlerTest(unittest.TestCase):
         except ValueError:
             pass
 
-    def test_handling_unknown_request_returns_none(self):
-        result = self.h.handle_request('an unhandled request')
-        self.assertFalse(result)
+    def test_handling_unknown_request_raises_exception(self):
+        try:
+            result = self.h.handle_request('an unhandled request')
+            self.fail(u'An unknown request should raise an exception')
+        except MpdAckError:
+            pass
 
     def test_handling_known_request(self):
         expected = 'magic'
         handler._request_handlers['known request'] = lambda x: expected
         result = self.h.handle_request('known request')
-        self.assertEquals(expected, result)
+        self.assert_(u'OK' in result)
+        self.assert_(expected in result)
 
 class CommandListsTest(unittest.TestCase):
     def setUp(self):
         self.h = handler.MpdHandler(backend=DummyBackend())
 
-    def test_commandlist_begin(self):
-        self.h.handle_request(u'command_list_begin')
-        expected = 'magic'
-        handler._request_handlers['known request'] = lambda x: expected
-        result = self.h.handle_request('known request')
+    def test_command_list_begin(self):
+        result = self.h.handle_request(u'command_list_begin')
         self.assert_(result is None)
 
-    def test_commandlist_end(self):
-        expected = 'magic'
-        self.test_commandlist_begin()
+    def test_command_list_end(self):
+        self.h.handle_request(u'command_list_begin')
         result = self.h.handle_request(u'command_list_end')
-        self.assert_(expected, result)
+        self.assert_(u'OK' in result)
+
+    def test_command_list_with_ping(self):
+        self.h.handle_request(u'command_list_begin')
+        self.assertEquals([], self.h.command_list)
+        self.assertEquals(False, self.h.command_list_ok)
+        self.h.handle_request(u'ping')
+        self.assert_(u'ping' in self.h.command_list)
+        result = self.h.handle_request(u'command_list_end')
+        self.assert_(u'OK' in result)
+        self.assertEquals(False, self.h.command_list)
+
+    def test_command_list_ok_begin(self):
+        result = self.h.handle_request(u'command_list_ok_begin')
+        self.assert_(result is None)
+
+    def test_command_list_ok_with_ping(self):
+        self.h.handle_request(u'command_list_ok_begin')
+        self.assertEquals([], self.h.command_list)
+        self.assertEquals(True, self.h.command_list_ok)
+        self.h.handle_request(u'ping')
+        self.assert_(u'ping' in self.h.command_list)
+        result = self.h.handle_request(u'command_list_end')
+        self.assert_(u'list_OK' in result)
+        self.assert_(u'OK' in result)
+        self.assertEquals(False, self.h.command_list)
+        self.assertEquals(False, self.h.command_list_ok)
 
 
 class StatusHandlerTest(unittest.TestCase):
@@ -50,22 +77,24 @@ class StatusHandlerTest(unittest.TestCase):
 
     def test_clearerror(self):
         result = self.h.handle_request(u'clearerror')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_currentsong(self):
         result = self.h.handle_request(u'currentsong')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_idle_without_subsystems(self):
         result = self.h.handle_request(u'idle')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_idle_with_subsystems(self):
         result = self.h.handle_request(u'idle database playlist')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_stats(self):
         result = self.h.handle_request(u'stats')
+        self.assert_(u'OK' in result)
+        result = result[0]
         self.assert_('artists' in result)
         self.assert_(int(result['artists']) >= 0)
         self.assert_('albums' in result)
@@ -83,6 +112,8 @@ class StatusHandlerTest(unittest.TestCase):
 
     def test_status(self):
         result = self.h.handle_request(u'status')
+        self.assert_(u'OK' in result)
+        result = dict(result)
         self.assert_('volume' in result)
         self.assert_(int(result['volume']) in xrange(0, 101))
         self.assert_('repeat' in result)
@@ -109,82 +140,84 @@ class PlaybackOptionsHandlerTest(unittest.TestCase):
 
     def test_consume_off(self):
         result = self.h.handle_request(u'consume "0"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_consume_on(self):
         result = self.h.handle_request(u'consume "1"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_crossfade(self):
         result = self.h.handle_request(u'crossfade "10"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_random_off(self):
         result = self.h.handle_request(u'random "0"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_random_on(self):
         result = self.h.handle_request(u'random "1"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_repeat_off(self):
         result = self.h.handle_request(u'repeat "0"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_repeat_on(self):
         result = self.h.handle_request(u'repeat "1"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_setvol_below_min(self):
         result = self.h.handle_request(u'setvol "-10"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_setvol_min(self):
         result = self.h.handle_request(u'setvol "0"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_setvol_middle(self):
         result = self.h.handle_request(u'setvol "50"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_setvol_max(self):
         result = self.h.handle_request(u'setvol "100"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_setvol_above_max(self):
         result = self.h.handle_request(u'setvol "110"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_single_off(self):
         result = self.h.handle_request(u'single "0"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_single_on(self):
         result = self.h.handle_request(u'single "1"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_replay_gain_mode_off(self):
         result = self.h.handle_request(u'replay_gain_mode off')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_replay_gain_mode_track(self):
         result = self.h.handle_request(u'replay_gain_mode track')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_replay_gain_mode_album(self):
         result = self.h.handle_request(u'replay_gain_mode album')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_replay_gain_status_default(self):
         expected = u'off'
         result = self.h.handle_request(u'replay_gain_status')
-        self.assertEquals(expected, result)
+        self.assert_(u'OK' in result)
+        self.assert_(expected in result)
 
     def test_replay_gain_status_off(self):
         expected = u'off'
         self.h._replay_gain_mode(expected)
         result = self.h.handle_request(u'replay_gain_status')
-        self.assertEquals(expected, result)
+        self.assert_(u'OK' in result)
+        self.assert_(expected in result)
 
     #def test_replay_gain_status_track(self):
     #    expected = u'track'
@@ -206,43 +239,43 @@ class PlaybackControlHandlerTest(unittest.TestCase):
 
     def test_next(self):
         result = self.h.handle_request(u'next')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_pause_off(self):
         result = self.h.handle_request(u'pause "0"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
         self.assertEquals(self.b.PLAY, self.b.state)
 
     def test_pause_on(self):
         result = self.h.handle_request(u'pause "1"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
         self.assertEquals(self.b.PAUSE, self.b.state)
 
     def test_play(self):
         result = self.h.handle_request(u'play "0"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
         self.assertEquals(self.b.PLAY, self.b.state)
 
     def test_playid(self):
         result = self.h.handle_request(u'playid "0"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
         self.assertEquals(self.b.PLAY, self.b.state)
 
     def test_previous(self):
         result = self.h.handle_request(u'previous')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_seek(self):
         result = self.h.handle_request(u'seek 0 30')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_seekid(self):
         result = self.h.handle_request(u'seekid 0 30')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_stop(self):
         result = self.h.handle_request(u'stop')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
         self.assertEquals(self.b.STOP, self.b.state)
 
 
@@ -252,51 +285,57 @@ class CurrentPlaylistHandlerTest(unittest.TestCase):
 
     def test_add(self):
         result = self.h.handle_request(u'add "file:///dev/urandom"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_addid_without_songpos(self):
         result = self.h.handle_request(u'addid "file:///dev/urandom"')
-        self.assert_('id' in result)
+        self.assert_(u'OK' in result)
+        result = result[0]
+        self.assert_(u'id' in result)
+
+        self.assert_(u'id' in result)
 
     def test_addid_with_songpos(self):
         result = self.h.handle_request(u'addid "file:///dev/urandom" 0')
-        self.assert_('id' in result)
+        self.assert_(u'OK' in result)
+        result = result[0]
+        self.assert_(u'id' in result)
 
     def test_clear(self):
         result = self.h.handle_request(u'clear')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_delete_songpos(self):
         result = self.h.handle_request(u'delete 5')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_delete_open_range(self):
         result = self.h.handle_request(u'delete 10:')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_delete_closed_range(self):
         result = self.h.handle_request(u'delete 10:20')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_deleteid(self):
         result = self.h.handle_request(u'deleteid 0')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_move_songpos(self):
         result = self.h.handle_request(u'move 5 0')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_move_open_range(self):
         result = self.h.handle_request(u'move 10: 0')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_move_closed_range(self):
         result = self.h.handle_request(u'move 10:20 0')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_moveid(self):
         result = self.h.handle_request(u'moveid 0 10')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_playlist_returns_same_as_playlistinfo(self):
         playlist_result = self.h.handle_request(u'playlist')
@@ -305,63 +344,63 @@ class CurrentPlaylistHandlerTest(unittest.TestCase):
 
     def test_playlistfind(self):
         result = self.h.handle_request(u'playlistfind tag needle')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_playlistid_without_songid(self):
         result = self.h.handle_request(u'playlistid')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_playlistid_with_songid(self):
         result = self.h.handle_request(u'playlistid "10"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_playlistinfo_without_songpos_or_range(self):
         result = self.h.handle_request(u'playlistinfo')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_playlistinfo_with_songpos(self):
         result = self.h.handle_request(u'playlistinfo "5"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_playlistinfo_with_open_range(self):
         result = self.h.handle_request(u'playlistinfo "10:"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_playlistinfo_with_closed_range(self):
         result = self.h.handle_request(u'playlistinfo "10:20"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_playlistsearch(self):
         result = self.h.handle_request(u'playlistsearch tag needle')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_plchanges(self):
         result = self.h.handle_request(u'plchanges "0"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_plchangesposid(self):
         result = self.h.handle_request(u'plchangesposid 0')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_shuffle_without_range(self):
         result = self.h.handle_request(u'shuffle')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_shuffle_with_open_range(self):
         result = self.h.handle_request(u'shuffle 10:')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_shuffle_with_closed_range(self):
         result = self.h.handle_request(u'shuffle 10:20')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_swap(self):
         result = self.h.handle_request(u'swap 10 20')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_swapid(self):
         result = self.h.handle_request(u'swapid 10 20')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
 
 class StoredPlaylistsHandlerTest(unittest.TestCase):
@@ -370,48 +409,48 @@ class StoredPlaylistsHandlerTest(unittest.TestCase):
 
     def test_listplaylist(self):
         result = self.h.handle_request(u'listplaylist name')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_listplaylistinfo(self):
         result = self.h.handle_request(u'listplaylistinfo name')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_listplaylists(self):
         result = self.h.handle_request(u'listplaylists')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_load(self):
         result = self.h.handle_request(u'load "name"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_playlistadd(self):
         result = self.h.handle_request(
             u'playlistadd name "file:///dev/urandom"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_playlistclear(self):
         result = self.h.handle_request(u'playlistclear name')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_playlistdelete(self):
         result = self.h.handle_request(u'playlistdelete name 5')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_playlistmove(self):
         result = self.h.handle_request(u'playlistmove name 5a 10')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_rename(self):
         result = self.h.handle_request(u'rename name new_name')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_rm(self):
         result = self.h.handle_request(u'rm name')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_save(self):
         result = self.h.handle_request(u'save name')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
 
 class MusicDatabaseHandlerTest(unittest.TestCase):
@@ -420,51 +459,57 @@ class MusicDatabaseHandlerTest(unittest.TestCase):
 
     def test_count(self):
         result = self.h.handle_request(u'count tag needle')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_find_album(self):
         result = self.h.handle_request(u'find album what')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_find_artist(self):
         result = self.h.handle_request(u'find artist what')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_find_title(self):
         result = self.h.handle_request(u'find title what')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_find_else_should_fail(self):
-        result = self.h.handle_request(u'find somethingelse what')
-        self.assert_(result is False)
+        try:
+            result = self.h.handle_request(u'find somethingelse what')
+            self.fail('Find with unknown type should fail')
+        except MpdAckError:
+            pass
 
     def test_findadd(self):
         result = self.h.handle_request(u'findadd album what')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_list_artist(self):
         result = self.h.handle_request(u'list artist')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_list_artist_with_artist_should_fail(self):
-        result = self.h.handle_request(u'list artist anartist')
-        self.assert_(result is False)
+        try:
+            result = self.h.handle_request(u'list artist anartist')
+            self.fail(u'Listing artists filtered by an artist should fail')
+        except MpdAckError:
+            pass
 
     def test_list_album_without_artist(self):
         result = self.h.handle_request(u'list album')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_list_album_with_artist(self):
         result = self.h.handle_request(u'list album anartist')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_listall(self):
         result = self.h.handle_request(u'listall "file:///dev/urandom"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_listallinfo(self):
         result = self.h.handle_request(u'listallinfo "file:///dev/urandom"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_lsinfo_without_path_returns_same_as_listplaylists(self):
         lsinfo_result = self.h.handle_request(u'lsinfo')
@@ -473,7 +518,7 @@ class MusicDatabaseHandlerTest(unittest.TestCase):
 
     def test_lsinfo_with_path(self):
         result = self.h.handle_request(u'lsinfo ""')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_lsinfo_for_root_returns_same_as_listplaylists(self):
         lsinfo_result = self.h.handle_request(u'lsinfo "/"')
@@ -482,41 +527,52 @@ class MusicDatabaseHandlerTest(unittest.TestCase):
 
     def test_search_album(self):
         result = self.h.handle_request(u'search "album" "analbum"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_search_artist(self):
         result = self.h.handle_request(u'search "artist" "anartist"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_search_filename(self):
         result = self.h.handle_request(u'search "filename" "afilename"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_search_title(self):
         result = self.h.handle_request(u'search "title" "atitle"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_search_else_should_fail(self):
-        result = self.h.handle_request(u'search "sometype" "something"')
-        self.assert_(result is False)
+        try:
+            result = self.h.handle_request(u'search "sometype" "something"')
+            self.fail(u'Search with unknown type should fail')
+        except MpdAckError:
+            pass
 
     def test_update_without_uri(self):
         result = self.h.handle_request(u'update')
+        self.assert_(u'OK' in result)
+        result = result[0]
         self.assert_('updating_db' in result)
         self.assert_(result['updating_db'] >= 0)
 
     def test_update_with_uri(self):
         result = self.h.handle_request(u'update "file:///dev/urandom"')
+        self.assert_(u'OK' in result)
+        result = result[0]
         self.assert_('updating_db' in result)
         self.assert_(result['updating_db'] >= 0)
 
     def test_rescan_without_uri(self):
         result = self.h.handle_request(u'rescan')
+        self.assert_(u'OK' in result)
+        result = result[0]
         self.assert_('updating_db' in result)
         self.assert_(result['updating_db'] >= 0)
 
     def test_rescan_with_uri(self):
         result = self.h.handle_request(u'rescan "file:///dev/urandom"')
+        self.assert_(u'OK' in result)
+        result = result[0]
         self.assert_('updating_db' in result)
         self.assert_(result['updating_db'] >= 0)
 
@@ -543,23 +599,23 @@ class ConnectionHandlerTest(unittest.TestCase):
 
     def test_close(self):
         result = self.h.handle_request(u'close')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_empty_request(self):
         result = self.h.handle_request(u'')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_kill(self):
         result = self.h.handle_request(u'kill')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_password(self):
         result = self.h.handle_request(u'password "secret"')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
     def test_ping(self):
         result = self.h.handle_request(u'ping')
-        self.assert_(result is None)
+        self.assert_(u'OK' in result)
 
 class AudioOutputHandlerTest(unittest.TestCase):
     def setUp(self):
@@ -574,6 +630,8 @@ class ReflectionHandlerTest(unittest.TestCase):
 
     def test_urlhandlers(self):
         result = self.h.handle_request(u'urlhandlers')
+        self.assert_(u'OK' in result)
+        result = result[0]
         self.assert_('dummy:' in result)
 
     pass # TODO