diff --git a/ssh-message-types.rkt b/ssh-message-types.rkt
index d1ced6b..2742456 100644
--- a/ssh-message-types.rkt
+++ b/ssh-message-types.rkt
@@ -236,6 +236,10 @@
 (define-ssh-message-type ssh-msg-disconnect SSH_MSG_DISCONNECT
   (uint32 reason-code)
   (string description)
+  ;; TODO: OpenSSH 5.3p1 Debian-3ubuntu7 25 Mar 2009 (from lucid)
+  ;; sends SSH_MSG_DISCONNECT without the language-tag field! In
+  ;; particular, when I press ^D to terminate my session, I get
+  ;; #"\1\0\0\0\v\0\0\0\24disconnected by user".
   (string language-tag))
 
 (define-ssh-message-type ssh-msg-unimplemented SSH_MSG_UNIMPLEMENTED