diff --git a/telethon/network/mtproto_sender.py b/telethon/network/mtproto_sender.py
index bf79910f..023a7734 100755
--- a/telethon/network/mtproto_sender.py
+++ b/telethon/network/mtproto_sender.py
@@ -192,16 +192,6 @@ class MtProtoSender:
         if code == 0xa7eff811:  # bad_msg_notification
             return self.handle_bad_msg_notification(msg_id, sequence, reader)
 
-        if code == 0x62d6b459:  # msgs_ack, it may handle the request we wanted
-            ack = reader.tgread_object()
-            for message_id in ack.msg_ids:
-                if message_id in self.need_confirmation:
-                    self.need_confirmation.remove(message_id)
-
-            if request and request.msg_id in ack.msg_ids:
-                request.confirm_received = True
-            return False
-
         # If the code is not parsed manually, then it was parsed by the code generator!
         # In this case, we will simply treat the incoming TLObject as an Update,
         # if we can first find a matching TLObject
diff --git a/telethon/telegram_client.py b/telethon/telegram_client.py
index 162bf39f..022c3003 100644
--- a/telethon/telegram_client.py
+++ b/telethon/telegram_client.py
@@ -1,7 +1,7 @@
 import platform
 from datetime import datetime
 from hashlib import md5
-from os import path, listdir
+from os import path
 from mimetypes import guess_extension, guess_type
 
 # For sending and receiving requests
@@ -35,7 +35,7 @@ from telethon.tl.all_tlobjects import layer
 class TelegramClient:
 
     # Current TelegramClient version
-    __version__ = '0.6'
+    __version__ = '0.5'
 
     # region Initialization
 
@@ -182,7 +182,8 @@ class TelegramClient:
     def log_out(self):
         """Logs out and deletes the current session. Returns True if everything went OK"""
         try:
-            self.invoke(LogOutRequest())
+            # This request is a bit special. Nothing is received after
+            self.sender.send(LogOutRequest())
             if not self.session.delete():
                 return False
 
@@ -190,13 +191,6 @@ class TelegramClient:
         except:
             return False
 
-    @staticmethod
-    def list_sessions():
-        """Lists all the sessions of the users who have ever connected
-           using this client and never logged out"""
-        return [path.splitext(path.basename(f))[0]  # splitext = split ext (not spli text!)
-                for f in listdir('.') if f.endswith('.session')]
-
     # endregion
 
     # region Dialogs ("chats") requests