diff --git a/shadowsocks/tcprelay.py b/shadowsocks/tcprelay.py
index 08fb2f5..b378107 100644
--- a/shadowsocks/tcprelay.py
+++ b/shadowsocks/tcprelay.py
@@ -45,11 +45,13 @@ CMD_UDP_ASSOCIATE = 3
 # stage 0 init
 # stage 1 hello received, hello sent
 # stage 2 UDP assoc
+# stage 3 DNS
 # stage 4 addr received, reply sent
 # stage 5 remote connected
 
 # remote:
 # stage 0 init
+# stage 3 DNS
 # stage 4 addr received, reply sent
 # stage 5 remote connected