diff --git a/shadowsocks/tcprelay.py b/shadowsocks/tcprelay.py
index 2687a73..c26109f 100644
--- a/shadowsocks/tcprelay.py
+++ b/shadowsocks/tcprelay.py
@@ -223,6 +223,8 @@ class TCPRelayHandler(object):
         self.speed_tester_u = SpeedTester(config.get("speed_limit_per_con", 0))
         self.speed_tester_d = SpeedTester(config.get("speed_limit_per_con", 0))
         self._recv_pack_id = 0
+        self._udp_send_pack_id = 0
+        self._udpv6_send_pack_id = 0
 
     def __hash__(self):
         # default __hash__ is id / 16
@@ -338,14 +340,23 @@ class TCPRelayHandler(object):
                     connecttype, dest_addr, dest_port, header_length = header_result
                     addrs = socket.getaddrinfo(dest_addr, dest_port, 0,
                             socket.SOCK_DGRAM, socket.SOL_UDP)
-                    #logging.info('UDP over TCP sendto %s:%d %d bytes from %s:%d' % (dest_addr, dest_port, len(data), self._client_address[0], self._client_address[1]))
                     if addrs:
                         af, socktype, proto, canonname, server_addr = addrs[0]
                         data = data[header_length:]
                         if af == socket.AF_INET6:
                             self._remote_sock_v6.sendto(data, (server_addr[0], dest_port))
+                            if self._udpv6_send_pack_id == 0:
+                                addr, port = self._remote_sock_v6.getsockname()[:2]
+                                common.connect_log('UDPv6 sendto %s:%d from %s:%d by user %d' %
+                                    (server_addr[0], dest_port, addr, port, self._user_id))
+                            self._udpv6_send_pack_id += 1
                         else:
                             sock.sendto(data, (server_addr[0], dest_port))
+                            if self._udp_send_pack_id == 0:
+                                addr, port = sock.getsockname()[:2]
+                                common.connect_log('UDP sendto %s:%d from %s:%d by user %d' %
+                                    (server_addr[0], dest_port, addr, port, self._user_id))
+                            self._udp_send_pack_id += 1
 
             except Exception as e:
                 #trace = traceback.format_exc()
@@ -597,8 +608,9 @@ class TCPRelayHandler(object):
                 server_info.buffer_size = self._recv_buffer_size
             connecttype, remote_addr, remote_port, header_length = header_result
             if connecttype != 0:
-                common.connect_log('UDP over TCP by user %d' %
-                        (self._user_id, ))
+                pass
+                #common.connect_log('UDP over TCP by user %d' %
+                #        (self._user_id, ))
             else:
                 common.connect_log('TCP request %s:%d by user %d' %
                         (common.to_str(remote_addr), remote_port, self._user_id))
@@ -711,7 +723,6 @@ class TCPRelayHandler(object):
         if result:
             ip = result[1]
             if ip:
-
                 try:
                     self._stage = STAGE_CONNECTING
                     remote_addr = ip
diff --git a/shadowsocks/udprelay.py b/shadowsocks/udprelay.py
index 05ecee3..fa9f404 100644
--- a/shadowsocks/udprelay.py
+++ b/shadowsocks/udprelay.py
@@ -445,9 +445,9 @@ class UDPRelay(object):
         af, socktype, proto, canonname, sa = addrs[0]
         key = client_key(r_addr, af)
         client_pair = self._cache.get(key, None)
-        if not client_pair:
+        if client_pair is None:
             client_pair = self._cache_dns_client.get(key, None)
-        if not client_pair:
+        if client_pair is None:
             if self._forbidden_iplist:
                 if common.to_str(sa[0]) in self._forbidden_iplist:
                     logging.debug('IP %s is in forbidden list, drop' %
@@ -486,9 +486,6 @@ class UDPRelay(object):
                 user_id = self._listen_port
             else:
                 user_id = struct.unpack('<I', client_uid)[0]
-            common.connect_log('UDP data to %s:%d via port %d by UID %d' %
-                        (common.to_str(server_addr), server_port,
-                            self._listen_port, user_id))
         else:
             client, client_uid = client_pair
         self._cache.clear(self._udp_cache_size)
@@ -509,6 +506,10 @@ class UDPRelay(object):
         try:
             #logging.info('UDP handle_server sendto %s:%d %d bytes' % (common.to_str(server_addr), server_port, len(data)))
             client.sendto(data, (server_addr, server_port))
+            if client_pair is None: # new request
+                addr, port = client.getsockname()[:2]
+                common.connect_log('UDP data to %s:%d from %s:%d by UID %d' %
+                        (common.to_str(server_addr), server_port, addr, port, user_id))
             self.add_transfer_u(client_uid, len(data))
         except IOError as e:
             err = eventloop.errno_from_exception(e)