diff --git a/CHANGES.rst b/CHANGES.rst
index d525babd1..60b46c0a3 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -1,3 +1,9 @@
+**2016-07-12**
+
+*Released 4.3.4*
+
+- Fix proxy support with ``urllib3`` when proxy requires auth
+
 **2016-07-08**
 
 *Released 4.3.3*
diff --git a/telegram/__init__.py b/telegram/__init__.py
index 4b1b74f11..4c7d13aca 100644
--- a/telegram/__init__.py
+++ b/telegram/__init__.py
@@ -82,7 +82,7 @@ from .update import Update
 from .bot import Bot
 
 __author__ = 'devs@python-telegram-bot.org'
-__version__ = '4.3.3'
+__version__ = '4.3.4'
 __all__ = ['Audio', 'Bot', 'Chat', 'ChatMember', 'ChatAction', 'ChosenInlineResult',
            'CallbackQuery', 'Contact', 'Document', 'Emoji', 'File', 'ForceReply',
            'InlineKeyboardButton', 'InlineKeyboardMarkup', 'InlineQuery', 'InlineQueryResult',
diff --git a/telegram/utils/request.py b/telegram/utils/request.py
index 99539bfb8..1ace3fc4f 100644
--- a/telegram/utils/request.py
+++ b/telegram/utils/request.py
@@ -57,14 +57,17 @@ def _init_con_pool():
                   ])
     proxy_url = _get_con_pool_proxy()
     if not proxy_url:
-        mgr = urllib3.PoolManager
+        mgr = urllib3.PoolManager(**kwargs)
     else:
-        kwargs['proxy_url'] = proxy_url
         if _CON_POOL_PROXY_KWARGS:
             kwargs.update(_CON_POOL_PROXY_KWARGS)
-        mgr = urllib3.ProxyManager
+        mgr = urllib3.proxy_from_url(proxy_url, **kwargs)
+        if mgr.proxy.auth:
+            # TODO: what about other auth types?
+            auth_hdrs = urllib3.make_headers(proxy_basic_auth=mgr.proxy.auth)
+            mgr.proxy_headers.update(auth_hdrs)
 
-    _CON_POOL = mgr(**kwargs)
+    _CON_POOL = mgr
 
 
 def is_con_pool_initialized():