diff --git a/telegram/ext/conversationhandler.py b/telegram/ext/conversationhandler.py
index 8a950d402..6afa90575 100644
--- a/telegram/ext/conversationhandler.py
+++ b/telegram/ext/conversationhandler.py
@@ -215,9 +215,11 @@ class ConversationHandler(Handler):
         if new_state == self.END:
             if key in self.conversations:
                 del self.conversations[key]
+            else:
+                pass
 
         elif isinstance(new_state, Promise):
-            self.conversations[key] = (self.conversations[key], new_state)
+            self.conversations[key] = (self.conversations.get(key), new_state)
 
         elif new_state is not None:
             self.conversations[key] = new_state
diff --git a/tests/test_conversationhandler.py b/tests/test_conversationhandler.py
index 6f6cd4ba3..f9ee4623b 100644
--- a/tests/test_conversationhandler.py
+++ b/tests/test_conversationhandler.py
@@ -36,7 +36,7 @@ except ImportError:
 sys.path.append('.')
 
 from telegram import Update, Message, TelegramError, User, Chat, Bot
-from telegram.ext import *
+from telegram.ext import Updater, ConversationHandler, CommandHandler
 from tests.base import BaseTest
 from tests.test_updater import MockBot
 
@@ -109,6 +109,9 @@ class ConversationHandlerTest(BaseTest, unittest.TestCase):
     def start(self, bot, update):
         return self._set_state(update, self.THIRSTY)
 
+    def start_end(self, bot, update):
+        return self._set_state(update, self.END)
+
     def brew(self, bot, update):
         return self._set_state(update, self.BREWING)
 
@@ -161,6 +164,48 @@ class ConversationHandlerTest(BaseTest, unittest.TestCase):
         sleep(.1)
         self.assertRaises(KeyError, self._get_state, user_id=second_user.id)
 
+    def test_endOnFirstMessage(self):
+        self._setup_updater('', messages=0)
+        d = self.updater.dispatcher
+        user = User(first_name="Misses Test", id=123)
+
+        handler = ConversationHandler(
+            entry_points=[CommandHandler('start', self.start_end)], states={}, fallbacks=[])
+        d.add_handler(handler)
+        queue = self.updater.start_polling(0.01)
+
+        # User starts the state machine and immediately ends it.
+        message = Message(0, user, None, None, text="/start")
+        queue.put(Update(update_id=0, message=message))
+        sleep(.1)
+        self.assertEquals(len(handler.conversations), 0)
+
+    def test_endOnFirstMessageAsync(self):
+        self._setup_updater('', messages=0)
+        d = self.updater.dispatcher
+        user = User(first_name="Misses Test", id=123)
+
+        start_end_async = (lambda bot, update: d.run_async(self.start_end, bot, update))
+
+        handler = ConversationHandler(
+            entry_points=[CommandHandler('start', start_end_async)], states={}, fallbacks=[])
+        d.add_handler(handler)
+        queue = self.updater.start_polling(0.01)
+
+        # User starts the state machine with an async function that immediately ends the
+        # conversation. Async results are resolved when the users state is queried next time.
+        message = Message(0, user, None, None, text="/start")
+        queue.put(Update(update_id=0, message=message))
+        sleep(.1)
+        # Assert that the Promise has been accepted as the new state
+        self.assertEquals(len(handler.conversations), 1)
+
+        message = Message(0, user, None, None, text="resolve promise pls")
+        queue.put(Update(update_id=0, message=message))
+        sleep(.1)
+        # Assert that the Promise has been resolved and the conversation ended.
+        self.assertEquals(len(handler.conversations), 0)
+
 
 if __name__ == '__main__':
     unittest.main()